NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD MAY 9, 2018

To our Stockholders:

We cordially invite you to attend the 2018 annual meeting of stockholders of Compass Minerals International, Inc. The meeting will take place at our headquarters, located at 9900 West 109^th Street, Suite 100, Overland Park, Kansas 66210, on Wednesday, May 9, 2018, at 9:00 a.m. We look forward to your attendance either in person or by proxy.

At the meeting, our stockholders will be asked to consider and act upon the following items of business:

Only stockholders of record as of the close of business on March 12, 2018, may vote at the meeting or any postponements or adjournments of the meeting. We have elected to provide access to our proxy materials over the Internet under the Securities and Exchange Commission’s “notice and access” rules again this year. This process reduces the costs of printing and distributing our proxy materials while reducing the environmental impact of our annual meeting. If you would like more information, please see the Questions and Answers section of this proxy statement.

Your vote is very important. Please vote regardless of whether or not you plan to attend our annual meeting.

By Order of the Board of Directors,

Diana C. Toman

Senior Vice President, General Counsel

and Secretary

March 27, 2018

To make it easier for you to review the proxy statement and vote, we offer four options:

Important Notice Regarding the Availability of Proxy Materials: This Notice of Meeting, this Proxy Statement and our 2017 Annual Report are available at www.proxyvote.com (with your investor identification number) and www.compassminerals.com.

PROXY STATEMENT SUMMARY

This summary highlights information contained elsewhere in this Proxy Statement. It does not contain all of the information you should consider, and you should read the entire Proxy Statement carefully before voting. References in this Proxy Statement to the “Company,” “Compass Minerals,” “we,” “us” and “our” refer to Compass Minerals International, Inc.

2018 Annual Meeting of Stockholders

Voting Matters and our Board of Director’s Recommendation

In addition to these matters, stockholders may be asked to vote on such other business as may properly come before our 2018 annual meeting of stockholders (the “Annual Meeting”).

Director Nominees

Stockholders are being asked to elect David J. D’Antoni, Allan R. Rothwell and Lori A. Walker as directors, who have each been nominated by our Board of Directors (our “Board of Directors” or “Board”).

Our stockholders expect our Board to oversee management performance, ensure the long-term interests of our stockholders are being served, monitor risks and adherence to our policies and perform the duties and responsibilities assigned to our Board under our Bylaws, Corporate Governance Guidelines and the laws of the State of Delaware, our state of incorporation. To fulfill these responsibilities, our Board is committed to being comprised of directors who bring diverse attributes, backgrounds, viewpoints and perspectives. We believe each of our directors’ qualifications add to the overall performance of our Board. The following table and charts provide an overview of each of our directors, including our three nominees. Additional information about each director’s background and experience can be found in the “2018 Nominees for Director and Continuing Directors” section of this Proxy Statement.

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Our Board of Directors

Qualification And Attributes:

Business/Functional Leader (9 Directors)

Industry Knowledge (4 Directors)

Sales and Marketing (8 Directors)

Diversity (4 Directors)

International Business (8 Directors)

Strategy/M&A (9 Directors)

Financial Experts (2 Directors)

Risk Management (8 Directors)

Talent Development (2 Directors)

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Board Snapshot

Corporate Governance Highlights

Our Board of Directors places great value on strong governance controls and regularly evaluates and implements emerging best practices. Set forth below are key highlights of our corporate governance practices that are further discussed beginning on page 15 of this Proxy Statement:

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Advisory Approval of Executive Compensation

Stockholders are being asked to approve, on an advisory basis, the compensation of our NEOs, commonly referred to as a “say-on-pay vote.” Our Board and the Compensation Committee value the opinions expressed by our stockholders and will continue to consider the results of this say-on-pay vote when evaluating our executive compensation program in the future.

Executive Compensation Highlights

Our executive compensation program is designed to promote stockholder interests by aligning our compensation with the realization of our business objectives and stockholder value. Set forth below are key highlights of our executive compensation program that are further discussed in the “Compensation Discussion and Analysis” section of this Proxy Statement:

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Ratification of Auditors

Stockholders are being asked to ratify the selection of Ernst & Young as our independent registered accounting firm for 2018.

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TABLE OF CONTENTS

COMPASS MINERALS INTERNATIONAL, INC.

9900 West 109^th Street, Suite 100

Overland Park, Kansas 66210

(913) 344-9200

2018 PROXY STATEMENT

Compass Minerals is a leading provider of essential minerals that solve nature’s challenges, including salt for winter roadway safety and other consumer, industrial and agricultural uses; specialty plant nutrition minerals that improve the quality and yield of crops; and specialty chemicals for water treatment and other industrial processes. As of December 31, 2017, we operated 22 production and packaging facilities, including:

We provide highway deicing salt and other salt products to customers in the United States, Canada and the U.K. Our plant nutrition business produces and markets specialty plant nutrition products worldwide to distributors and retailers of crop inputs, as well as growers. Our principal plant nutrition product in North America is SOP. In October 2016, we significantly expanded our plant nutrition business with the acquisition of Produquímica Indústria e Comércio S.A. (“Produquímica”), which operates two primary businesses in Brazil – agricultural productivity, which manufactures and distributes a broad offering of specialty plant nutrition solution-based products, and chemical solutions, which manufactures and markets specialty chemicals, primarily for the chemical and industrial markets and for use in the water treatment industry. In the U.K., we operate a records management business utilizing excavated areas of our Winsford salt mine with one other location in London, England.

Our Board of Directors is providing you this Proxy Statement in connection with the solicitation of proxies on its behalf for the Annual Meeting. The meeting will take place at our headquarters, 9900 West 109^th Street, Suite 100, Overland Park, Kansas 66210 on Wednesday, May 9, 2018 at 9:00 a.m. local time. At the meeting, stockholders will vote on the election of three directors, advisory approval of the compensation of our NEOs and ratification of the appointment of Ernst & Young as our independent registered accounting firm for 2018. In addition, stockholders will transact any other business that may properly come before the meeting, although we know of no other business to be presented.

By submitting your proxy, you authorize Diana C. Toman and Zoe A. Vantzos, both officers of Compass Minerals, to represent you and vote your shares at the meeting in accordance with your instructions. If you do not provide instructions, they will vote your shares consistent with the Board’s recommendations. They also may vote your shares to adjourn the meeting and will be authorized to vote your shares at any postponements or adjournments of the meeting. Please note that if you are a beneficial owner of shares, you must obtain a legal proxy from the record holder and bring it to the meeting in order to vote in person.

Our proxy materials include this Proxy Statement, our 2017 Annual Report to Stockholders (the “Annual Report”), which includes our Annual Report on Form 10-K for the fiscal year ended December 31, 2017, as well as the proxy card or a voting instruction form. The Annual Report and the information contained on our website do not constitute a part of the proxy solicitation materials and are not incorporated by reference into this Proxy Statement.

YOUR VOTE IS VERY IMPORTANT. WHETHER OR NOT YOU PLAN TO ATTEND THE ANNUAL MEETING, WE ENCOURAGE YOU TO READ THIS PROXY STATEMENT AND SUBMIT YOUR PROXY OR VOTING INSTRUCTIONS AS SOON AS POSSIBLE.

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QUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING

What is the purpose of the Annual Meeting?

The purpose of the Annual Meeting is to consider and act upon the following proposals:

Members of our management team and representatives of Ernst & Young are expected to be present at the Annual Meeting to respond to questions from stockholders.

Why did I receive a one-page notice in the mail regarding the Internet availability of proxy materials instead of a full set of proxy materials?

In accordance with rules adopted by the Securities and Exchange Commission (the “SEC”), we have elected to provide access to our proxy materials over the Internet. Accordingly, we are sending a Notice of Internet Availability of Proxy Materials (the “Notice of Internet Availability”) to our stockholders. All stockholders will have the ability to access the proxy materials on the website referred to in the Notice of Internet Availability or request to receive a printed set of the proxy materials. Instructions on how to access the proxy materials over the Internet or to request a printed copy may be found in the Notice of Internet Availability. In addition, stockholders may request to receive proxy materials in printed form by mail or electronically by email on an ongoing basis.

How can I get electronic access to the proxy materials?

The Notice of Internet Availability will provide you with instructions regarding how to view our proxy materials for the Annual Meeting on the Internet and how to instruct us to send future proxy materials, including the Notice of Internet Availability, to you electronically by email. Our proxy materials are also available on our website at www.compassminerals.com.

What does it mean if I receive more than one Notice of Internet Availability of Proxy Materials or proxy card?

It means that your shares are held in more than one account at the transfer agent and/or with banks or brokers. Please vote all of your shares by voting by telephone or Internet with respect to each Notice of Internet Availability you receive, or by completing and returning each proxy card you receive.

How can I request and receive a paper or email copy of the proxy materials?

You may request and receive a paper or email copy of the proxy materials at no cost at www.proxyvote.com, by telephone at 1-800-579-1639, or by email at sendmaterial@proxyvote.com. In each case, you will need your 16-digit investor identification number from the Notice of Internet Availability to request the materials.

Who is entitled to vote?

The record date for the meeting was March 12, 2018. Only stockholders of record at the close of business on that date are entitled to vote at the meeting. Each outstanding share of common stock is entitled to one vote for all matters before the meeting. At the close of business on the record date, there were 33,831,815 shares of our common stock outstanding.

Am I entitled to vote if my shares are held in “street name”?

If your shares are held by a bank or brokerage firm, you are considered the “beneficial owner” of shares held in “street name.” If your shares are held in street name, the Notice of Internet Availability is being forwarded to you by your bank or

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brokerage firm (the “record holder”). If you request printed copies of the proxy materials by mail, you will receive a voting instruction form from the record holder. As the beneficial owner, you have the right to direct your record holder how to vote your shares and the record holder is required to vote your shares in accordance with your instructions. If you do not give instructions to your bank or brokerage firm, it will nevertheless be entitled to vote your shares with respect to “routine” items but will not be permitted to vote your shares with respect to “non-routine” items. In the case of a “non-routine” item, your shares will be considered “broker non-votes” on that proposal.

As the beneficial owner of shares, you are invited to attend the Annual Meeting. If you are a beneficial owner, however, you may not vote your shares in person at the meeting unless you obtain a legal proxy from the record holder of your shares and bring it to the Annual Meeting with photo identification.

Which ballot measures are considered “routine” or “non-routine”?

The vote to ratify the appointment of Ernst & Young as our independent registered accounting firm for 2018 (Proposal No. 3) is considered routine under applicable rules. A broker or other nominee may generally vote on routine matters, and therefore no broker non-votes are expected to exist in connection with Proposal No. 3.

The election of directors (Proposal No. 1) and the advisory approval of our NEO compensation (Proposal No. 2) are considered non-routine under applicable rules. A broker or other nominee cannot vote without instructions on non-routine matters, and therefore broker non-votes may exist for Proposals No. 1 and No. 2. It is important that you vote or direct the voting of your stock.

How many shares must be present to hold the meeting?

A quorum must be present at the meeting for any business to be conducted. The presence at the meeting, in person or by proxy, of the holders of a majority of the shares of common stock outstanding on the record date will constitute a quorum. Proxies received but marked as abstentions or treated as broker non-votes will be included in the calculation of the number of shares considered to be present at the meeting.

Who may attend the Annual Meeting?

All our stockholders as of the record date, March 12, 2018, may attend the Annual Meeting.

What if a quorum is not present at the Annual Meeting?

If a quorum is not present at the scheduled time of the Annual Meeting, a majority vote of the stockholders who are represented at the meeting may adjourn the meeting until a quorum is present. The time and place of the adjourned meeting will be announced at the time the adjournment is taken and no other notice will be given unless the adjourned meeting is more than 30 days later or a new record date is fixed.

What if I do not return my proxy and do not attend the Annual Meeting?

If you are a record holder (that is, your shares are registered in your own name with our transfer agent) and you do not vote your shares, your shares will not be voted at the Annual Meeting.

If you hold your shares in “street name,” and you do not give your bank, broker, or other holder of record specific voting instructions for your shares at the Annual Meeting, your record holder can vote your shares on the ratification of the independent registered accounting firm (Proposal No. 3). However, your record holder cannot vote your shares without your specific instructions on the election of directors (Proposal No. 1) or the advisory approval of our NEO compensation (Proposal No. 2), so it is important that you provide such voting instructions.

For the proposals listed above for which a bank or broker cannot vote without your instruction, if you do not provide voting instructions to your bank or broker on such proposals, the votes will be considered “broker non-votes” and will not be counted in determining the outcome of the vote. “Broker non-votes” will be counted as present for purposes of determining whether a quorum is present to hold the Annual Meeting.

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How do I vote?

Who will count the votes?

Broadridge Financial Services, Inc. will tabulate the votes.

How does the Board of Directors recommend I vote on the proposals?

Our Board recommends that you vote:

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What if I do not specify how my shares are to be voted?

Your vote will be considered cast as follows:

Will any other business be conducted at the Annual Meeting?

We know of no other business that will be presented at the Annual Meeting. However, if any other matter properly comes before the stockholders for a vote at the Annual Meeting, the proxy holders will vote your shares in accordance with their best judgment.

What happens if a nominee is unable to stand for election?

If a nominee is unable to stand for election, the Board of Directors may either reduce the number of directors to be elected or select a substitute nominee. If a substitute nominee is selected, the proxy holders will vote your shares for the substitute nominee.

What is the voting requirement to approve each of the proposals?

In the election of directors, each director will be elected by the affirmative vote of a majority of the votes cast at the meeting with respect to that director nominee. In other words, each nominee will be elected if the number of votes cast “for” the nominee’s election exceeds the votes cast “against” the nominee’s election. Approval of each of the other proposals requires the affirmative vote of a majority of the shares present, in person or represented by proxy, and entitled to vote on that proposal at the Annual Meeting.

How will broker non-votes and abstentions be treated?

The table below summarizes the treatment of abstentions and broker non-votes for each proposal that will be brought before the Annual Meeting.

Where can I find the voting results of the Annual Meeting?

We plan to announce preliminary voting results at the Annual Meeting and to publish final results in a Current Report on Form 8-K filed with the SEC no later than May 15, 2018. After the Form 8-K is filed, you may obtain a copy by visiting our website.

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PROPOSAL 1—ELECTION OF DIRECTORS

Current Nominees

Our Board of Directors currently consists of nine directors divided into three classes (Class I, Class II and Class III). Directors in each class are elected to serve three-year terms that expire in successive years. The terms of the Class III directors will expire at the upcoming Annual Meeting.

Our Board of Directors has nominated each of David J. D’Antoni, Allan R. Rothwell and Lori A. Walker for election as Class III directors for three-year terms expiring at the annual meeting of stockholders to be held in 2021 or until their successors are elected and qualified. Mr. D’Antoni, Mr. Rothwell and Ms. Walker currently serve as Class III directors.

Each nominee has consented to being named in this Proxy Statement and has agreed to serve, if elected. If a nominee is unable to stand for election, our Board may either reduce the number of directors to be elected or select a substitute nominee. If a substitute nominee is selected for any nominee, the proxy holders will vote your shares for the substitute nominee.

Vote Required

Each director will be elected by the affirmative vote of a majority of the votes cast at the meeting with respect to that director nominee. This means that each nominee will be elected if the number of votes cast “for” the nominee’s election exceeds the votes cast “against” the nominee’s election. Abstentions and broker non-votes will have no effect on the election of any nominee.

THE BOARD OF DIRECTORS RECOMMENDS THAT YOU VOTE “FOR” THE

ELECTION OF EACH OF THE THREE NOMINEES.

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2018 NOMINEES FOR DIRECTOR AND CONTINUING DIRECTORS

The following tables sets forth, for each of our director nominees and continuing directors, his or her name, age at the time of the Annual Meeting, principal occupation and employment during the past five years, the year in which he or she first became our director and directorships held in other public companies during the past five years as well as the experience, qualifications, attributes and skills that support their service as a director.

NOMINEES FOR ELECTION AS CLASS III DIRECTORS

FOR A THREE-YEAR TERM EXPIRING AT THE 2021 ANNUAL MEETING

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CLASS I DIRECTORS CONTINUING IN OFFICE

WHOSE TERMS EXPIRE AT THE 2019 ANNUAL MEETING

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CLASS II DIRECTORS CONTINUING IN OFFICE

WHOSE TERMS EXPIRE AT THE 2020 ANNUAL MEETING

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BOARD OF DIRECTORS AND BOARD COMMITTEES

Role of the Board of Directors

Our Board is elected by our stockholders to oversee our management, to help ensure we meet our responsibilities to our stockholders and to build long-term growth in stockholder value. Beyond its general oversight of management, our Board performs a number of critical roles in our strategic planning process, our enterprise risk management processes, selecting the CEO and executive officer succession planning. Our Board has adopted Corporate Governance Guidelines, which are available on our website at www.compassminerals.com.

Board Leadership

Our Board has a Lead Independent Director and does not have a Chairman of the Board of Directors. The Lead Independent Director is elected annually by our Board and, in May 2017, our Board elected Mr. Grant to serve in this role. Mr. Grant has served as the Lead Independent Director since the position was created in May 2005, except during his short service as our Interim Chief Executive Officer.

Under our Corporate Governance Guidelines, the Lead Independent Director’s duties and responsibilities include:

Our Board believes that its leadership structure is effective. The current structure appropriately allows full discussion of significant issues, supported by input from our management. Board meeting agendas are built around an annual Board-approved matrix of topics with additional elements developed jointly by the CEO and the Lead Independent Director with input from other directors. Board meetings are led by the CEO with significant input from the Lead Independent Director.

Our Board regularly considers whether our leadership structure is appropriate and has concluded that our structure remains appropriate given our specific circumstances, including the established effectiveness of the Lead Independent Director’s role on our Board, the Governance Committee’s significant role in the nominee selection process for new or re- elected directors, the independence of all eight non-employee directors, the effectiveness and frequency of the executive sessions of non-employee directors and the strong, independent, clearly defined Lead Independent Director duties and responsibilities set forth in our Corporate Governance Guidelines.

In 2017, our Board updated our Corporate Governance Guidelines to include a succession plan for our Lead Independent Director. As specified in these Guidelines, in the event our Lead Independent Director is unable to serve in this capacity, the chair of the Governance Committee would serve as the Lead Independent Director until the independent Board members select a new Lead Independent Director.

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Director Independence

Our Board evaluates the independence of its members at least annually and at other appropriate times when a change in circumstances could potentially impact the independence of a director (for example, if a director changes employment). In making independence determinations, our Board applies the independence requirements of the New York Stock Exchange (“NYSE”). Under NYSE rules, a director is independent if the director does not have a disqualifying relationship, as described in the NYSE rules, and our Board affirmatively determines that the director has no material relationship with us, either directly or as an officer, stockholder or partner of an organization that has a relationship with us.

As a result of its annual independence evaluation, our Board determined that each of our current directors, David J. D’Antoni, Valdemar L. Fischer, Eric Ford, Richard S. Grant, Allan R. Rothwell, Lori A. Walker, Paul S. Williams and Amy J. Yoder, are independent directors. Francis J. Malecha, our CEO, is not an independent director because he is a Company employee.

Board and Committee Meetings, Executive Sessions and Attendance

Our Board is active and engaged. Board agendas are set in advance by the Lead Independent Director and the CEO to ensure appropriate topics are covered and there is sufficient time for discussion. Directors are provided comprehensive materials in advance of Board and Board committee meetings and are expected to review these materials in advance of meetings to ensure our meetings are focused on active discussions instead of lengthy presentations.

Our Board meets regularly throughout the year and held four meetings in 2017. At each of these meetings, our non-employee directors held executive sessions, without the CEO or other Company employees present. Under our Corporate Governance Guidelines, our Board is required to hold at least four executive sessions per year with independent and non-employee directors, without the CEO or other Company employees present. The Lead Independent Director is responsible for coordinating, developing the agenda and presiding at these executive sessions.

During 2017, each director attended at least 75% of all Board meetings and meetings of each Board committee on which he or she served during 2017. Under our Corporate Governance Guidelines, directors are expected to attend each annual meeting of stockholders and all of our directors attended our 2017 annual meeting of stockholders. The membership of each Board committee as of the date of this Proxy Statement and the number of 2017 meetings and executive sessions of the Board and each Board committee are shown in the table below.

*  Independent Director    ** Audit Committee Financial Expert

Board Committees

Our Board has four standing committees: the Audit Committee, the Compensation Committee, the Governance Committee and the EHS Committee. Each Board committee operates under a written charter adopted by our Board, which is

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available on the Investor Relations section of our website at www.compassminerals.com. Each Board committee has the authority to retain advisors, at our expense, to assist the committee in performing its functions. At each Board and Board committee meeting, our non-employee directors held executive sessions, without the CEO or other Company employees present.

Audit Committee. The Audit Committee assists our Board with its oversight responsibilities regarding the integrity of our financial statements, the adequacy and effectiveness of our accounting and financial controls and the performance of our internal audit function and independent auditor. In addition, our Audit Committee oversees our compliance with legal and regulatory requirements, our enterprise risk management process and compliance with our Code of Ethics and Business Conduct. The Audit Committee’s functions are further described under “Report of the Audit Committee.”

Our Board has determined that each member of the Audit Committee is independent under NYSE and SEC rules and is financially literate, knowledgeable and qualified to review financial statements. Our Board also determined that Mr. Rothwell and Ms. Walker are each an “audit committee financial expert,” as defined by SEC rules. The Audit Committee held eight meetings in 2017, each with an executive session.

Compensation Committee. The Compensation Committee reviews and approves the compensation for our executive officers, including our CEO, approves all equity awards and other bonus awards to employees, and reviews our Board’s compensation. The Compensation Committee also oversees the application of our compensation clawback policy and our stock ownership guidelines and reviews risks related to our compensation policies and practices. The Compensation Committee’s functions are further described under “Compensation Discussion and Analysis.” Our Board has determined that each member of the Compensation Committee is independent under NYSE and SEC rules. The Compensation Committee held five meetings in 2017, each with an executive session.

Nominating/Corporate Governance Committee. The Governance Committee is responsible for considering, assessing and making recommendations concerning director nominees; reviewing the size, structure and composition of our Board and Board committees; conducting the annual review of the Lead Independent Director, overseeing our corporate governance and reviewing and approving any related party transactions. The Governance Committees’ functions are further described on pages 17-18. Our Board determined that each member of the Governance Committee is independent under NYSE rules. The Governance Committee held four meetings in 2017, each with an executive session.

Environmental, Health and Safety Committee. The EHS Committee is responsible for oversight related to environmental, health and safety, including our objectives, policies, procedures and performance, our risks and risk management and our compliance with applicable laws. The EHS Committee also reviews our sustainability efforts and reporting. The EHS Committee held four meetings in 2017, each with an executive session.

Board Role in Risk Oversight

Our Board’s role in our risk management process is one of oversight. Risk management activities are the responsibility of our management and include the development of strategies and actions to anticipate, identify, assess, manage and appropriately mitigate identified risks. The independent structure of our Board enables objective oversight of the risk management process.

Our management has implemented an enterprise risk management process, which is designed to identify and assess risk and to develop strategies and policies regarding risk acceptance, reduction, mitigation or avoidance. An overview of the findings of this enterprise risk management process and our top-identified risks is presented periodically to our Board, providing our Board an opportunity to inquire and provide guidance on our risk management activities. Our strategic plans, which our Board regularly discusses with our management, also reflect the findings of our enterprise risk management process.

Board committees are provided with more specific information on our risks and risk mitigation activities relating to their respective area of responsibility. The Audit Committee reviews the enterprise risk management process, our major financial risk exposures and steps taken by our management to monitor and control those exposures. In addition, the Compensation Committee reviews risks related to our compensation policies and practices and the Governance Committee oversees matters related to our governance risks. Our Board recognizes the environmental, health and safety risks that are inherent in our business and actively oversees our compliance with environmental, health and safety initiatives through its EHS Committee.

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Compensation Policies and Practices Related to Risk Management

The Compensation Committee reviewed our compensation policies and practices for employees and determined that these policies and practices do not create risks that are reasonably likely to have a material adverse effect on us. This review and risk assessment included an inventory of incentive plans and programs and considered factors such as the number of participants, performance metrics, maximum payments and risk mitigation features. In addition, the Compensation Committee, with the assistance of Pearl Meyer, our independent compensation consultant, assesses and considers potential risks when reviewing and approving our compensation policies and practices.

Our executive compensation program, described in detail in “Compensation Discussion and Analysis,” has risk mitigation features, including:

Majority Voting in Uncontested Director Elections and Director Resignation Policy

Under our Bylaws, in an uncontested election of directors (i.e., one where the number of director nominees does not exceed the number of directors to be elected), each director will be elected by a majority of the votes cast. This means the number of votes cast “for” a nominee’s election must exceed the number of votes cast “against” the nominee’s election. In a contested election of directors (i.e., one where the number of director nominees exceeds the number of directors to be elected), each director will be elected by a plurality vote. This means the nominees receiving the highest number of votes cast “for” will be elected even if a nominee receives less than a majority of the votes cast.

Under our Corporate Governance Guidelines, in an uncontested election of directors, any director nominee who receives a greater number of “against” votes than “for” votes, must promptly tender his or her resignation to our Board. The Governance Committee and our Board would then consider whether to accept or reject the tendered resignation and take appropriate action in accordance with our Corporate Governance Guidelines.

In addition, pursuant to our Corporate Governance Guidelines, directors are required to resign from their position as a member of our Board effective at the annual meeting of stockholders falling after his or her 75^th birthday.

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Service on Other Boards of Directors

Service by our Board members on the boards of directors of other companies provides valuable governance and leadership experience that ultimately benefits us. However, this service may require a commitment of significant time and attention. As a result, under our Corporate Governance Guidelines, non-employee directors may sit on no more than five boards of directors of for-profit companies (including our Board), without the approval of our Board. Our CEO must obtain approval of our Board before serving on a board of directors of any for-profit company. Currently, none of our non-employee directors sit on more than five board of directors of for-profit companies (including our Board), and our CEO does not sit on the board of directors of any for-profit company, other than our Board.

Board Evaluation Process

Our Corporate Governance Guidelines require annual evaluations of the performance of the Board, Board committees and individual directors, including the Lead Independent Director and the CEO. As part of the annual evaluation process, directors are able to provide feedback on the performance of other directors and the effectiveness of the Board and each Board committee, as well as compliance of each Board committee with its charter. The evaluations are reviewed each year and are modified as appropriate to ensure the evaluations focus on director contributions and performance in light of our business and strategies.

Our Board and each Board committee reviews its evaluation results and performance, and our Board reviews the evaluation results and performance of individual directors, including our CEO. Our Governance Committee reviews the evaluation results and performance of our Lead Independent Director. In addition, each director receives feedback based on the evaluation results from the Lead Independent Director or the Chair of the Governance Committee. The evaluation results for each director are shared with the Governance Committee for its review of potential nominees for election as a director.

Succession Planning

Each year, our Board works with our management to review succession and development plans for the CEO and all other executive officers. Several times per year, our CEO discusses Company leadership and talent development with our Board. Our Board members become familiar with potential successors for our executive officers and other key leaders through various means, including presentations to the Board and informal meetings. In addition, succession planning and talent development discussions are embedded in our leadership and performance management processes. We develop our talent capability through job rotations and experiences, new tools, training and hiring outside talent with a diversity of backgrounds and skills. Our management has developed and maintains an emergency succession plan for key positions, including the CEO and other executive officers, that is reviewed at least annually with our Board.

CORPORATE GOVERNANCE

Code of Ethics and Business Conduct

We have adopted a Code of Ethics and Business Conduct (our “Code of Ethics”) for our directors, officers and employees. Our Code of Ethics is reviewed each year for appropriate updates and directors, officers and salaried employees are asked to annually certify their understanding and compliance with our Code of Ethics. Our Code of Ethics, which is grounded in our Core Values, is made available to our employees in English, Brazilian Portuguese and French Canadian and is available on our website at www.compassminerals.com.

Only our Board or a designated Board committee may grant waivers of our Code of Ethics for our directors and executive officers. We intend to disclose any changes in, or waivers from, our Code of Ethics by posting such information on www.compassminerals.com or by filing a Current Report on Form 8-K, in each case if such disclosure is required by SEC or NYSE rules. No waivers of our Code of Ethics were granted to directors or officers in 2017.

Corporate Responsibility and Sustainability

We have a clear vision of our corporate purpose. Through the minerals we mine and harvest and the products we produce, we help keep people safe, feed the world and enrich lives every day. We are committed to our stockholders,

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employees and the communities in which we operate to building a sustainable company, to ensuring safety throughout our operations, to being responsible stewards of the resources we manage and to minimizing or mitigating our environmental impact where possible.

Sustainability for Compass Minerals also means pursuing a strategy to achieve long-term growth to drive strong financial results and returns for our stockholders. It also means doing all of this with transparency and accountability. These concepts form the four points of our sustainability compass; safety, growth, stewardship and transparency. As we build our company, innovate and bring new products to market, we always keep this compass in mind. Our people are critical to all the points of this compass.   Our Board reviews our sustainability reporting, targets and goals as well as our progress toward achievement of these targets and goals, with the EHS Committee focused on environmental, health and safety matters, the Compensation Committee focused on social and diversity matters and the Governance committee focused on governance matters.

In addition, our pay-for-performance philosophy motivates our executive officers to operate our business in a profitable and sustainable matter. This includes having executive officer personal objectives for our MAIP that include safety improvement goals as we work to strengthen our overall culture of safety and diversity improvement goals as we work to build a diverse and inclusive culture.

For additional information about our sustainability efforts, including our sustainability targets and goals, please read our Sustainability Report, which is available on our website at www.compassminerals.com.

Anti-Hedging and Pledging Policy

All directors, executive officers and employees are prohibited from engaging in short sales of our securities and from buying, selling or investing in Company-based derivative securities, including entering into any hedging transactions with respect to our securities or engaging in comparable transactions. Directors and executive officers are also prohibited from pledging any Company securities (i.e., using our common stock as collateral for a loan or to trade shares on margin).

Stock Ownership Guidelines

Our Compensation Committee has adopted a policy requiring each director and member of our senior management to obtain and maintain ownership in our common stock (or its equivalent) at specified levels. In 2017, the Stock Ownership Guidelines were updated to, among other items, clarify that if an individual falls below his or her stock ownership guideline, the individual will not be required to purchase additional shares to meet the ownership guideline, but will be required to retain all net shares received from vesting or payment of our common stock until the applicable ownership guideline is achieved, and must continue to maintain this level of share ownership. For purposes of the Stock Ownership Guidelines, restricted stock units, earned performance stock units and deferred stock units count toward the ownership achievement. The ownership requirements are summarized in the following table:

As of March 2018, all directors and executive officers have met their requirements under the Stock Ownership Guidelines, or were still within their five-year window to achieve compliance, other than Mr. Malecha and Steven N. Berger, Senior Vice President, Corporate Services. They have not met the requirements under the Stock Ownership Guidelines due to declines in our stock price and because performance stock units granted in 2013, 2014 and 2015 vested below their target levels in 2016, 2017 and 2018, consistent with our pay-for-performance philosophy. Neither Mr. Malecha or Mr. Berger have sold any shares of our stock since joining us in January 2013 and March 2013, respectively, other than shares sold to pay applicable withholding taxes in connection with the vesting of equity awards.

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Director Selection Process and Qualifications

The Governance Committee is responsible for reviewing the composition of our Board and recommending to our Board director candidates for nomination and election at the annual stockholder meeting and to fill Board vacancies.

The Governance Committee annually reviews with the Board the size and composition of our Board, focusing on the interplay of each director’s and director nominee’s experience, qualifications, attributes and skills with the Board as a whole and the Company’s needs. In making its recommendations to our Board regarding the composition of our Board and the nomination of director candidates, the Governance Committee considers the qualifications of individual director candidates applying the Board membership criteria described below.

While the selection of qualified directors is a complex, subjective process that requires consideration of many intangible factors, our Board believes that diversity is an important attribute of a well-functioning board and our Governance Committee should consider diversity in the director identification and nomination process. Our Corporate Governance Guidelines provide that our Governance Committee and our Board should seek to achieve a mix of directors that represents a diversity of attributes, background, experiences (including experience with businesses and other organizations of a comparable complexity), perspectives and skills, including with respect to differences in customs, culture, international background, thought, generational views, race, gender and specialized professional experience. Our Board also considers diversity when selecting directors for Board leadership positions.

In addition, our Corporate Governance Guidelines sets forth the following minimum qualifications for a director (i) personal integrity; (ii) a degree from an accredited college or university or equivalent professional experience; (iii) five years’ successful experience in a senior responsible position; (iv) good communication skills; (v) practical, mature business judgment; (vi) experience in analyzing corporate financial statements; (vii) experience and effectiveness working closely with a team of senior professionals; (viii) available time to dedicate to the position; (ix) the absence of conflicts of interest; and (x) an understanding of organizational structure and accountability, delegation of authority, compensation practices, and the dynamics of competitive businesses.

If a vacancy arises or our Board decides to expand its membership, the Governance Committee, with the involvement of the Lead Independent Director and the CEO, will seek recommendations of potential candidates from incumbent directors, our stockholders, our management, third-party search firms and other sources. The Governance Committee will then evaluate each potential candidate on the basis of the qualifications, skills and attributes set forth in our Corporate Governance Guidelines. The Governance Committee seeks to identify and recruit the best available candidates and will evaluate qualified stockholder candidates on the same basis as those submitted by other sources.

At the Governance Committee’s direction, we retained Heidrick & Struggles International, Inc. (“Heidrick”), an independent third-party search firm, to assist us in the process of identifying a new Board member with significant multinational leadership experience with agribusinesses in Latin America coupled with the highest standards of personal and professional integrity. A search committee appointed by our Board, which was composed of the Lead Independent Director, Chair of the Governance Committee and a member of the Governance Committee, interviewed several candidates submitted by Heidrick. Based upon Mr. Fischer’s qualifications and independence, the search committee recommended to the Governance Committee that our Board be expanded to nine members, appoint Mr. Fischer as a Class II director and to nominate him to stand for election at our 2017 annual meeting of stockholders. Our Board appointed Mr. Fischer as a director on February 1, 2017, and he was elected by stockholders at our 2017 annual meeting of stockholders.

Procedures for Nominations of Director Candidates by Stockholders

The Governance Committee will consider director candidates submitted by our stockholders using the same criteria described above. Our Bylaws also allow our stockholders to nominate candidates for election as a director by following the procedures and delivering the information required by our Bylaws to 9900 West 109^th Street, Suite 100, Overland Park, Kansas 66210, Attn: Secretary.

Stockholders who wish to nominate candidates for election at our 2019 annual meeting of stockholders must deliver a stockholder’s notice with the information required by our Bylaws between January 8, 2019 and February 7, 2019. However, if the 2019 annual meeting is held more than 30 days before or after the anniversary of the 2018 annual meeting, then, to be timely, the stockholder’s notice must be delivered not earlier than the close of business on the 120^th day prior to the 2019 annual meeting and not later than the close of business on the later of the 90^th day prior to the 2019 annual meeting or, if later, the 10^th day following the day on which we first make a public announcement of the date of such meeting.

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In addition, our Bylaws permit stockholders to propose additional matters for consideration at our annual meetings of stockholders by following the procedures and delivering the information required by our Bylaws. For more information, see “Additional Filings and Information—Stockholder Proposals for 2019 Annual Meeting.”

Review and Approval of Transactions with Related Persons

Our Board has adopted a written policy and procedures for review, approval and monitoring of transactions involving us and “related persons” (directors, director nominees, executive officers, their immediate family members and stockholders owning 5% or greater of our outstanding stock). The policy covers any related-person transaction that meets or is near the minimum threshold for disclosure in our proxy statement under relevant SEC rules (generally, transactions involving amounts exceeding $120,000 in which a related person has a direct or indirect material interest).

Under the Board’s policy and procedures, the Governance Committee will review the material facts of all proposed related-party transactions. In determining whether to approve or ratify a related-party transaction, the Governance Committee will take into account, among other factors it deems appropriate, whether the related-party transaction is on terms no less favorable to us than terms generally available to an unaffiliated third party under the same or similar circumstances and the extent of the related party’s interest in the transaction.

In 2017, there were no transactions involving us and related persons that required review by the Governance Committee or disclosure in this Proxy Statement.

Communications with our Board of Directors

Stockholders or others who wish to communicate with our Board or any individual director (including the Lead Independent Director) should direct their comments to 9900 West 109^th Street, Suite 100, Overland Park, Kansas 66210, Attn: Secretary. The Company’s Secretary will forward any communications (excluding routine advertisements, business solicitations and communications that the Secretary deems to be a security risk or harassment) to each member of our Board or, if applicable, to the individual directors named in the correspondence. If the correspondence is directed to the Lead Independent Director or the non-employee members of our Board as a group, the Company’s Secretary will first receive the approval of the Lead Independent Director before disclosing or otherwise discussing the communication with other members of our management, including our CEO.

Compensation Committee Interlocks and Insider Participation

During 2017, the Compensation Committee consisted of Mr. Williams (chair), Mr. Fischer, Mr. Grant, Ms. Walker and Ms. Yoder. No person who served as a member of the Compensation Committee during 2017 was a current or former officer or employee of the Company, or engaged in certain transactions with us required to be disclosed as “related person transactions” under SEC regulations. There were no compensation committee “interlocks” during 2017, which generally means that none of our executive officers served as a director or member of the compensation committee of another entity, one of whose executive officers served as a member of our Board or as a member of the Compensation Committee.

2017 NON-EMPLOYEE DIRECTOR COMPENSATION

Philosophy and Objectives

Our non-employee director compensation program is designed to attract and retain well-qualified directors with appropriate skill sets to meet our evolving needs. Our Board considers and determines non-employee director compensation each year, taking into account recommendations from the Compensation Committee and our independent compensation consultant, Pearl Meyer. The Compensation Committee formulates its recommendation to our Board based on its review and analysis of Pearl Meyer’s report on director compensation practices for a specific group of peer companies, which our Board also reviews when making determinations regarding director compensation. A discussion of our peer group begins on page 30.

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2017 Compensation

For 2017, non-employee directors received the following compensation:

Non-employee director compensation is paid in quarterly installments, is prorated based on the relevant dates of service and is paid pursuant to our Non-Employee Director Compensation Policy, which was adopted effective January 1, 2017. Mr. Malecha, our CEO, does not receive any additional compensation for serving as a director.

Non-employee director compensation in 2017 remained the same as 2016 compensation, with the exception of an increase of the annual Lead Independent Director fee from $20,000 in 2016 to $25,000 in 2017. The Board, based on the recommendation of the Compensation Committee and Pearl Meyer, increased this fee because it had been below the comparable fees paid by our 2017 peer group companies. The Compensation Committee and our Board reviewed and analyzed Pearl Meyer’s report on director compensation practices for our 2018 peer companies and determined to make no changes to non-employee director compensation for 2018.

Cash Compensation. In addition to the $75,000 annual retainer, non-employee directors receive fees for serving as Board committee chairs or members and as Lead Independent Director due to the workload and responsibilities of these positions. The following table summarizes fees paid for 2017 service on Board committees:

Equity Compensation. Non-employee directors receive an equity award with an annual value of $85,000, which is paid either in shares of our common stock or, at the director’s election, in deferred stock units. Non-employee directors who have not met the requirements of our Stock Ownership Guidelines are required to defer their equity award in the form of deferred stock units. All equity awards to our non-employee directors vest immediately on grant.

Deferral of Compensation. Non-employee directors may elect to defer all or a portion of their cash and equity compensation. Any cash compensation that is deferred is converted into deferred stock units. As dividends are paid on our common stock, deferred stock units accrue dividends in the form of additional deferred stock units, which have a value equivalent to our common stock. Accumulated deferred stock units are distributed in the form of our common stock at the time the director ceases to be a member of our Board or such other dates elected by the director.

The following table summarizes the total compensation paid to or earned by non-employee directors for 2017.

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2017 NON-EMPLOYEE DIRECTOR COMPENSATION TABLE

(1)  Includes cash compensation that was deferred in the form of deferred stock units.

(2)  Includes equity compensation that was paid in the form of shares of our common stock and deferred stock units. The amounts represent the grant date fair value recognized in accordance with ASC Topic 718. The number of shares of common stock and deferred stock units granted was based on the market value of our common stock on each grant date.

(3)  Prorated based on dates of service as chair of the Governance Committee. Mr. D’Antoni served in this capacity until May 2, 2017 and thereafter Ms. Yoder served in this capacity.

(4)  Prorated based on joining our Board on February 1, 2017.

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STOCK OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth certain information provided to us with respect to beneficial ownership of shares of our common stock as of March 9, 2018 (except where another date is indicated) for (i) each person who is known by us to own beneficially more than 5% of our outstanding shares of common stock, (ii) each current director and nominee for director, (iii) each NEO, and (iv) all our current directors and executive officers as a group.

*  Each having less than 1% of our issued and outstanding common stock.

(1)  For purposes of this table, information as to the percentage of shares beneficially owned is calculated based on 33,831,815 shares of our common stock outstanding on March 9, 2018, except that the ownership percentages shown for owners of more than 5% of our common stock are based on the respective Schedule 13G and 13G/A Information Statements for December 31, 2017. The amounts and percentages of common stock beneficially owned are reported as determined by SEC rules and include voting or investment power with respect to the shares on the basis of SEC rules governing the determination of beneficial ownership of securities. Except as otherwise indicated in these footnotes, each of the beneficial owners has, to our knowledge, sole voting and investment power with respect to the indicated shares of common stock.

(2)  Based on a Schedule 13G/A Information Statement filed by BlackRock, Inc. on January 19, 2018, for December 31, 2017, disclosing that BlackRock, Inc. has sole voting power over 3,540,195 shares of our common stock and sole dispositive power over 3,608,533 shares of our common stock, which represented 10.7% of our common stock at the time of filing. The 13G/A reports that beneficial owner subsidiaries of the parent holding company are BlackRock (Netherlands) B.V., BlackRock Advisors, LLC, BlackRock Asset Management Canada Limited, BlackRock Asset Management Ireland Limited, BlackRock Asset Management Schweiz AG, BlackRock Financial Management, Inc., BlackRock Fund Advisors, BlackRock Institutional Trust Company, National Association, BlackRock Investment Management (Australia) Limited, BlackRock Investment Management (UK) Limited, BlackRock Investment Management, LLC and BlackRock Life Limited.

(3)  Based on a Schedule 13G/A Information Statement filed by The Vanguard Group on February 9, 2018, for December 31, 2017, disclosing that The Vanguard Group has sole voting power over 64,146 shares of our common stock, shared voting power over 4,229 shares of our common stock, sole dispositive power over 3,079,954 shares of our common stock and shared dispositive power over 65,036 shares of our common stock, which

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represented 9.29% of our common stock at the time of filing. The 13G/A reports that beneficial owner subsidiaries of the parent investment advisor company are Vanguard Fiduciary Trust Company and Vanguard Investments Australia, Ltd.

(4)  Based on a Schedule 13G Information Statement filed by OppenheimerFunds, Inc. on February 7, 2018, for December 31, 2017, disclosing that OppenheimerFunds, Inc. has shared voting power and shared dispositive power over 1,912,663 shares of our common stock, which represented 5.65% of our common stock at the time of filing.

(5)  For our named executive officers and executive officers, number of shares beneficially owned includes beneficial ownership of stock options that were exercisable as of March 9, 2018 or within 60 days thereafter (as listed below), RSUs that vest within 60 days of March 9, 2018 (as listed below), 0% of PSUs that were granted in March 2015 and were due to vest in March 2018 and shares of our common stock held in employees’ 401(k) accounts. For Mr. Standen, number of shares beneficially owned includes PSUs that were granted in December 2016 and vested in March 2018, which are also included in the table below. For our directors, number of shares beneficially owned includes deferred stock units (as listed below).

(6)   Includes 15 shares of our common stock held jointly by Mr. Berger and his wife.

(7)   Includes 1,112 shares of our common stock held by Mr. D’Antoni’s wife and 2,575 shares of our common stock held by trust.

SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

Section 16(a) of the Exchange Act requires our directors, executive officers and persons who own more than 10% of our outstanding common stock to file with the SEC reports of their ownership of our common stock and furnish us with copies of these reports.

Based solely on a review of the copies of the reports furnished to us and written representations from our directors and executive officers that no additional reports were required, we believe that during 2017 all of our directors and executive officers complied with all applicable Section 16(a) filing requirements on a timely basis.

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PROPOSAL 2—ADVISORY APPROVAL OF EXECUTIVE COMPENSATION

Our stockholders are being asked to cast an advisory, non-binding vote to approve the compensation of our NEOs, commonly referred to as a “say-on-pay vote.” Our Board and the Compensation Committee, which administers our executive compensation program, value the opinions expressed by our stockholders and will continue to consider the outcome of these votes in making its decisions on executive compensation.

Our executive compensation program is designed to promote stockholder interests by aligning our compensation with the realization of our business objectives and stockholder value. Our Board believes our executive compensation program uses appropriate structures and sound pay practices that are effective in achieving our core objectives. We encourage stockholders to read the “Compensation Discussion and Analysis” section of this Proxy Statement beginning on page 24, which describes our executive compensation program in detail and decisions made by the Compensation Committee in 2017.

Our Board recommends that you vote in favor of the following advisory resolution:

“RESOLVED, that Compass Minerals International, Inc. stockholders approve, on an advisory basis, the compensation of the Company’s named executive officers, as disclosed pursuant to the Securities and Exchange Commission’s compensation disclosure rules (which disclosure includes the Compensation Discussion and Analysis and “Executive Compensation Tables” sections of the Company’s Proxy Statement).”

Vote Required

Approval of an advisory resolution to approve the compensation of our NEOs requires the affirmative vote of the holders of a majority of the shares of common stock present and entitled to vote at the Annual Meeting. Abstentions have the same effect as a vote against this proposal. Broker non-votes will have no effect on the outcome of this proposal. As an advisory vote, the outcome of the vote on this proposal will not be binding upon us, our Board or the Compensation Committee.

THE BOARD OF DIRECTORS RECOMMENDS THAT YOU VOTE “FOR” THE ADVISORY

APPROVAL OF THE COMPENSATION OF OUR NAMED EXECUTIVE OFFICERS.

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COMPENSATION DISCUSSION AND ANALYSIS

This section describes the material components and objectives of our executive compensation program for our NEOs, explaining how and why our Compensation Committee arrived at specific compensation practices and decisions for 2017 NEO compensation. For 2017, the NEOs whose compensation will be discussed in this section and their titles as of December 31, 2017, are the below-listed individuals.

2017 NAMED EXECUTIVE OFFICERS

Chief Financial Officer Transition. Mr. Standen was appointed as our Chief Financial Officer in August 2017, previously having served as our Interim Chief Financial Officer and Treasurer since April 2017 and, prior to this role, as our Vice President, Finance and Treasurer. Mr. Craft served as our Interim Chief Financial Officer from November 2016 until April 2017 and currently serves as our Vice President, Internal Audit. Mr. Linehan briefly served as our Chief Financial Officer during April 2017. The compensation of Mr. Craft and Mr. Linehan is discussed separately below. The discussion in the Compensation Discussion and Analysis does not otherwise relate to the compensation of Mr. Craft and Mr. Linehan, and references to NEOs in this section do not include Mr. Craft or Mr. Linehan.

EXECUTIVE SUMMARY

We view compensation practices as an avenue to communicate and reinforce our goals and standards of conduct, as well as a means to reward NEOs for their achievements. Our compensation philosophy is grounded in promoting stockholder interests by aligning compensation with the realization of our business objectives and increased long-term stockholder value. Under our compensation philosophy, we are committed to providing a competitive total compensation package that drives employee engagement and performance which, in turn, helps drive our business strategy and success.

2017 Company Performance. Compass Minerals has pursued a strategy to drive growth based on strengthening our safety culture, workforce engagement and asset longevity; increasing the balance between our two businesses–salt and plant nutrition; and driving margin improvement, organic growth and innovation to meet our customers’ needs. While our salt business faced the challenge of a second consecutive mild winter in 2017, the benefits of our strategy helped to mitigate the financial impact of lower Salt segment sales and earnings. Our 2017 business results are summarized below.

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Setting Executive Compensation. The performance of our executive officers is essential to achieving our goal of increasing stockholder value. To align executive officer interests with those of stockholders and to motivate and reward individual initiatives and effort, a significant portion of our NEOs’ compensation is at-risk and performance-based, with metrics aligned to the Company’s financial results and business strategy, with a clear connection to the NEO’s individual performance. Our executive compensation program is intended to offer an opportunity for gain in the event of successful performance against established criteria, balanced with the prospect of reduced compensation in the absence of success.

As we do every year, we ensured our compensation philosophy and compensation policies aligned with legal requirements and our objectives. In 2017, we have:

Our stockholders have consistently affirmed their support of our executive compensation program. At last year’s annual meeting of stockholders, 94.9% of the shares cast voted in favor of our say-on-pay proposal on NEO compensation. The Compensation Committee views this vote as supportive of our overall approach to executive officer compensation.

2017 Key Compensation Elements. The key elements of our executive compensation program did not change in 2017. These elements are described in detail starting on page 29 and are summarized below.

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Total direct compensation, which includes base salary, MAIP bonus payments and equity awards for our NEOs, is targeted to be near median levels for our selected market group, to provide a competitive compensation opportunity and to attract and retain executive talent. Our market group is comprised of a blend of our peer group companies and market data from reputable survey sources. In any given year or for any given NEO, some elements may be above or below median.

Linking Compensation to Performance. Our Compensation Committee designs our executive compensation program to appropriately align pay and performance, with a significant portion of executive compensation being at risk and performance-based. In addition, our Compensation Committee believes that executive officer compensation should be more heavily weighted toward variable compensation than the compensation of other employees. The rationale is that executive officer performance is more likely to have a strong and direct impact on strategic and financial goals likely to affect stockholder value. Our pay mix and design reflect these beliefs.

The charts below illustrate the 2017 total direct compensation mix at target for our CEO and the average of our other NEOs (other than Mr. Standen, who only served as an executive officer for a portion of 2017). Total direct compensation mix at target is comprised of (i) base pay as of December 31, 2017, (ii) 2017 MAIP bonus payments at target and (iii) target grant value of 2017 equity awards (our long-term incentive compensation). A large percentage of total direct compensation is at risk because all of our MAIP bonus payments and equity awards are variable, performance-based compensation.

EXECUTIVE COMPENSATION FRAMEWORK AND GOVERNANCE

Our executive compensation program is designed to promote stockholder interests by aligning compensation with the realization of our business objectives and increased long-term stockholder value. Under our compensation philosophy, we are committed to providing a competitive total compensation package that drives employee engagement and performance which, in turn, helps drive our business strategy and success. This commitment leads to compensation programs that are designed to:

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To achieve these compensation objectives, our executive compensation program is based on the following principles.

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Executive Compensation Practices. The Compensation Committee regularly discusses practices and corporate governance developments relating to executive officer compensation. The table below highlights our key executive compensation practices including the practices we have implemented because they support our desire to appropriately impact performance results and align with long-term stockholder interests, and practices we have not implemented because we do not believe they would serve our stockholders’ long-term interests.

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Further discussion on certain of these practices can be found in the “Other Compensation Policies and Practices” section, below.

Executive Compensation Program Summary

Direct Compensation Elements. We provide three elements in our executive compensation program to balance short-term rewards and long-term alignment with corporate strategy, stockholder interests and executive retention: base pay, MAIP and long-term incentive compensation in the form of equity grants. The following table summarizes the three compensation tools we use to attract, reward, align and retain our executive officers.

We also have the following executive compensation elements:

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Peer Groups and Benchmarking. The Compensation Committee, with assistance from Pearl Meyer, annually reviews specific criteria and recommendations regarding companies to add to or remove from our peer group. Pearl Meyer, at the direction of our Compensation Committee, utilized objective business and financial criteria to select for our 2017 peer group publicly-traded companies in the metals, mining, agriculture, chemical (including fertilizers and agricultural chemicals) and construction material industries with comparable pay models, revenues and company market capitalization values.

Based on its annual review and analysis of our peer group, Pearl Meyer recommended removing Cytec Industries Inc., OM Group Inc. and Walter Energy, Inc. from our peer group because they had been acquired or filed for bankruptcy in 2015. Pearl Meyer recommended adding Tronox Limited, Headwaters Incorporated and The Scotts Miracle-Gro Company to our 2017 peer group, which are each relevant from an industry perspective and are appropriate comparators in terms of company size.

Based on Pearl Meyer’s analysis and recommendations, the Compensation Committee approved the companies listed below for our 2017 peer group. At the time of review, all peer group companies were publicly-traded, stand-alone companies of appropriate size and within relevant industries that the Compensation Committee believed compete with us in labor markets and follow similar pay models, and had U.S.-based executives and executive compensation programs which appear to conform to typical U.S. practices. In addition, our market capitalization and revenue approximated the median of the 2017 peer group. All are U.S.-based and traded on NYSE or Nasdaq, except for Thompson Creek Metals Company Inc., a Canadian mining company purchased by a Canadian company, Centerra Gold, in October 2016 (Centerra Gold is traded on TSX but Thompson Creek Metals Company Inc. is no longer publicly traded).

2017 Peer Group Companies

With the assistance of Pearl Meyer, the Compensation Committee reviews a summary of compensation practices of our peer group and annually compares our three principal elements of executive compensation (base pay, annual incentive opportunity and long-term incentive compensation) with similar programs at our peer group companies to ensure our NEO total compensation is within a reasonably competitive range of our peers. The Compensation Committee also considers individual factors such as performance, responsibilities and experience. In setting 2017 compensation, the Compensation Committee also considered our market group, which is comprised of a blend of our peer group and market data from reputable survey sources. Our peer group data, along with market group data, is used to ensure we have an accurate size and scope of data for setting competitive pay positions for our executive officers.

In August 2017, the Compensation Committee decided to expand the size of our 2018 peer group to 27 companies, adding 16 companies and removing six companies, as listed below. The 2018 peer group will serve both for compensation purposes and for the comparator group to measure rTSR for our rTSR PSUs granted beginning in 2018.

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2018 Peer Group Companies

EXECUTIVE COMPENSATION DECISIONS FOR 2017

The Compensation Committee approves compensation awards that are not contingent on the number, term or current value of other compensation previously awarded to executive officers. The Compensation Committee is of the opinion that reducing or limiting current awards or other performance-based compensation because of prior gains realized would unfairly penalize the individual and reduce the motivation for high performance. Further, the Compensation Committee does not purposefully increase total longer-term compensation value in a given year to offset less than expected returns from previous awards.

Our Compensation Committee determines all compensation for executive officers. During the first quarter of each year, our Compensation Committee conducts an evaluation to determine if any changes in compensation are appropriate for any of our executive officers. This evaluation is based on a market analysis prepared by Pearl Meyer, individual performance and our overall financial performance, and, for each executive officer, the Compensation Committee considers this information to independently determine each component of compensation.

The CEO does not participate in the Compensation Committee’s deliberations or decisions with regard to his compensation. At our Compensation Committee’s request however, the CEO reviews with our Compensation Committee the performance of our other executive officers, but no other employee has any input into executive compensation decisions. The Compensation Committee gives considerable weight to the CEO’s evaluation of our other executive officers because of his direct knowledge of these individuals’ performance and contributions.

Base Salary. Base pay provides a fixed level of cash compensation for services rendered, competitive with base salaries within our market group. When setting NEO base pay, the Compensation Committee considered (i) the relationship between our base salary levels and the blended market level of the base salaries of our market group, with a view towards recruiting and retaining talent, and (ii) the experience, knowledge, responsibilities, skills, potential, time in position and performance of the individual NEO. For 2017, base pay was targeted near the 50^th percentile (median) of our market group. Actual base pay may be above or below the median depending on the Compensation Committee’s considerations. As a result of its review, the Compensation determined to increase base salaries for NEOs effective March 1, 2017 and to increase Mr. Standen’s base salary effective April 25, 2017, the date he assumed the role of Interim Chief Financial Officer and Treasurer.

The following table summarizes the changes to each NEO’s base pay in 2017.

(1)  Mr. Standen’s base pay was increased effective April 25, 2017 when he was named Interim Chief Financial Officer and Treasurer.

(2)  Mr. Sepich joined us in November 2016.

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2017 Management Annual Incentive Program

MAIP Overview. Annual cash bonuses are paid to our NEOs under the MAIP, which links a substantial portion of each NEO’s annual cash compensation to our financial performance and individual performance. These bonuses are designed to reward, where earned, short-term performance evidenced by the achievement of our annual operating plan’s goals and individual performance. Bonuses paid under the MAIP are variable and are determined by the Compensation Committee based on targets and performance factors set by the Compensation Committee at the beginning of the year. MAIP bonus payments are made under our 2015 Incentive Award Plan and are typically paid in March following the performance year; however, 2017 MAIP bonuses were paid in February 2018.

2017 MAIP Bonus Formula. In 2017, MAIP bonuses to our NEOs were calculated using the following formula.

MAIP Target Bonus Percentage. Target MAIP bonuses are based on a percentage of each NEO’s base salary. Actual MAIP bonuses may range from 0% to 200% of each NEO’s target MAIP bonus, depending on actual results achieved against the MAIP performance factors. The target MAIP bonus percentages are set by the Compensation Committee and intended to be market competitive and consistent with median short-term cash bonus percentages of our market group. The MAIP target percentages and target bonuses are set forth below. For 2017, the Compensation Committee, in consultation with Pearl Meyer, reviewed our executive’s total compensation to ensure appropriate alignment with our market group, to reflect the market for executive talent and to recognize individual performance and contribution to the Company. Based on this review, the Compensation Committee increased the MAIP target percentage for Mr. Berger by 5 percentage points with respect to 2017, as compared to 2016.

(1)  For purposes of calculating Mr. Standen’s target bonus, his target percentage and base salary were prorated for the time he was in his role as Vice President, Finance and Treasurer and his roles as Interim Chief Financial Officer and Treasurer and Chief Financial Officer. The base salary and target percentage listed for Mr. Standen are the annualized amounts based on this proration.

MAIP Performance Factors. For any MAIP bonus payments to be made, the Company must achieve Adjusted EBITDA of at least 75% of the pre-established Adjusted EBITDA target. If this hurdle is achieved, MAIP bonus payments for NEOs are based on the following performance factors (i) Adjusted EBITDA for the Company as a whole, for the Salt business unit and for the Plant Nutrition North America and South America business units, on a combined basis, which measure Company and business unit financial performance, and (ii) individual performance objectives, which measure personal performance. The table below outlines the rationale for using these performance factors.

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The percentage weighting of each performance metric is based on the NEO’s responsibilities, as outlined below.

(1)  For Mr. Standen, the Company Adjusted EBITDA performance factor is weighted at 70% and the individual performance factor is weighted at 30% for the time he was in his role as Vice President, Finance and Treasurer and the Company Adjusted EBITDA performance factor is weighted at 80% and the individual performance factor is weighted at 20% for the time he was in his roles as Interim Chief Financial Officer and Treasurer and Chief Financial Officer.

Financial Performance Factors. The Compensation Committee chose Adjusted EBITDA as the financial metric to measure Company and business unit performance for purposes of the NEO’s MAIP bonus payments for 2017. The Company performance factors and the targeted achievement levels were approved in the first quarter of 2017 and were chosen based on considerations that included 2016 results, a targeted improvement for 2017, the Board-approved 2017 annual operating plan and the anticipated 2017 business environment.

EBITDA stands for earnings before interest, taxes, depreciation and amortization. For MAIP and other compensation purposes, Adjusted EBITDA is calculated by adding restructuring charges to EBITDA. The Compensation Committee believes adjustments to EBITDA are appropriate to avoid the impact (positive or negative) on Company performance factor achievements that result from unusual or non-recurring items, or non-cash items or events not contemplated by our 2017 annual operating plan and to help ensure that management takes actions that will benefit the long-term performance of the Company despite potential short-term unfavorable impacts.

The Company performance factors are subject to a payout cap of 200% of target. The actual achievement of the Company performance factors are computed from our financial results as certified by the Chief Financial Officer using a linear calculation and the following payout scale. For 2017, the Compensation Committee reviewed the MAIP design and decided to recalibrate how MAIP payments were calculated to ensure the MAIP remains aligned with our pay-for-performance philosophy, changing the MAIP payout scale so that if 75% of a Company performance factor is achieved, the resulting Company performance factor achievement payout is 50% (rather than 25% in 2016) and if 120% of a Company performance factor is achieved (rather than 150% in 2016), the resulting Company performance factor achievement payout is at 200% of target.

In 2017, our Adjusted EBITDA performance was below target, as shown in the following table.

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Individual Performance Factor. The personal performance objectives for each of our NEOs are based on a combination of the current year and longer-term business goals, are both quantitative and qualitative in nature and include key Company strategic objectives specific to each individual’s area of responsibility and accountability. The table below provides a general description of the personal performance objectives for each of our NEOs. Certain personal performance objectives and specific targets are not disclosed because we believe this disclosure would reveal strategic objectives and information that is not otherwise publicly disclosed and would result in competitive harm.

After the end of the performance year, our CEO reviewed the individual performance of the other NEOs with the Compensation Committee and recommended an achievement level for the individual performance metric, which can range from 0% to 200%, based on the degree to which these NEOs achieved their personal performance objectives. The Compensation Committee also considered the performance of our CEO and determined his achievement level for the personal performance metric, which can range from 0% to 200%. In determining the individual performance factor achievement for each NEO, the Compensation Committee and our CEO did not place specific weighting on any one personal performance objective, but performed a holistic assessment of each individual NEO’s objectives, taking into account the relative importance of each objective to the Company’s strategic goals.

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MAIP Results. All MAIP bonuses are approved by the Compensation Committee following its review and approval of the financial performance factor achievement levels (which were certified by the Chief Financial Officer) and individual performance factor achievement levels. The following table shows the 2017 MAIP bonuses paid to NEOs.