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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                               ------------------

                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934

                             (Amendment No. 3 )*

                               ------------------

                            Navigant Consulting, Inc.
                            -------------------------
                                (Name of Issuer)

                                  Common Stock
                                  ------------
                         (Title of Class of Securities)

                                    63935N107
                                    ---------
                                 (CUSIP Number)

                                December 31, 2003
                                -----------------
             (Date of Event Which Requires Filing of this Statement)

        Check the appropriate box to designate the rule pursuant to which
                            this Schedule is filed:

                                [x] Rule 13d-1(b)
                                [ ] Rule 13d-1(c)
                                [ ] Rule 13d-1(d)

                               ------------------

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).

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                               Page 1 of 10 Pages



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CUSIP No. 63935N107                    13G                    Page 2 of 10 Pages
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1    NAME OF REPORTING PERSON
     S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

     Columbia Wanger Asset Management, L.P.  36-3820584
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2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                         (a) [ ]
          Not Applicable
                                                                         (b) [ ]
--------------------------------------------------------------------------------
3    SEC USE ONLY
--------------------------------------------------------------------------------
4    CITIZENSHIP OR PLACE OF ORGANIZATION

          Delaware
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                    5    SOLE VOTING POWER
NUMBER OF SHARES                  None
                    ------------------------------------------------------------
BENEFICIALLY        6    SHARED VOTING POWER
                                  1,861,000
OWNED BY
                    ------------------------------------------------------------
EACH                7    SOLE DISPOSITIVE POWER
                                  None
REPORTING
                    ------------------------------------------------------------
PERSON WITH         8    SHARED DISPOSITIVE POWER
                                  1,861,000
--------------------------------------------------------------------------------
9    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          1,861,000
--------------------------------------------------------------------------------
10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

          Not Applicable                                                     [ ]
--------------------------------------------------------------------------------
11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

               4.2%
--------------------------------------------------------------------------------
12   TYPE OF REPORTING PERSON

          IA
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--------------------------                           ---------------------------
CUSIP No. 63935N107                    13G                    Page 3 of 10 Pages
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1    NAME OF REPORTING PERSON
     S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

     WAM Acquisition GP, Inc.
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2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                         (a) [ ]
          Not Applicable
                                                                         (b) [ ]
--------------------------------------------------------------------------------
3    SEC USE ONLY
--------------------------------------------------------------------------------
4    CITIZENSHIP OR PLACE OF ORGANIZATION

          Delaware
--------------------------------------------------------------------------------
                    5    SOLE VOTING POWER
NUMBER OF SHARES                           None
                    ------------------------------------------------------------
BENEFICIALLY        6    SHARED VOTING POWER
                                      1,861,000
OWNED BY
                    ------------------------------------------------------------
EACH                7    SOLE DISPOSITIVE POWER
                                           None
REPORTING
                    ------------------------------------------------------------
PERSON WITH         8    SHARED DISPOSITIVE POWER
                                      1,861,000
--------------------------------------------------------------------------------
9    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          1,861,000
--------------------------------------------------------------------------------
10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

          Not Applicable                                                     [ ]
--------------------------------------------------------------------------------
11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

               4.2%
--------------------------------------------------------------------------------
12   TYPE OF REPORTING PERSON

          CO
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--------------------------                           ---------------------------
CUSIP No. 63935N107                    13G                    Page 4 of 10 Pages
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1    NAME OF REPORTING PERSON
     S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

     Columbia Acorn Trust
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2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                                                                         (a) [ ]
          Not Applicable
                                                                         (b) [ ]
--------------------------------------------------------------------------------
3    SEC USE ONLY
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4    CITIZENSHIP OR PLACE OF ORGANIZATION

          Massachusetts
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                    5    SOLE VOTING POWER
NUMBER OF SHARES              None
                    ------------------------------------------------------------
BENEFICIALLY        6    SHARED VOTING POWER
                              1,446,000
OWNED BY
                    ------------------------------------------------------------
EACH                7    SOLE DISPOSITIVE POWER
                              None
REPORTING
                    ------------------------------------------------------------
PERSON WITH         8    SHARED DISPOSITIVE POWER
                              1,446,000
--------------------------------------------------------------------------------
9    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          1,446,000
--------------------------------------------------------------------------------
10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

          Not Applicable                                                     [ ]
--------------------------------------------------------------------------------
11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

               3.2%
--------------------------------------------------------------------------------
12   TYPE OF REPORTING PERSON

          IV
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Item 1(a) Name of Issuer:

          Navigant Consulting, Inc.

Item 1(b) Address of Issuer's Principal Executive Offices:

          615 North Wabash Avenue
          Chicago, Illinois  60611

Item 2(a) Name of Person Filing:

          Columbia Wanger Asset Management, L.P. ("WAM")
          WAM Acquisition GP, Inc., the general partner of WAM
          ("WAM GP")
          Columbia Acorn Trust ("Acorn")

Item 2(b) Address of Principal Business Office:

          WAM, WAM GP and Acorn are all located at:

          227 West Monroe Street, Suite 3000
          Chicago, Illinois  60606

Item 2(c) Citizenship:

          WAM is a Delaware limited partnership; WAM
          GP is a Delaware corporation; and Acorn is a
          Massachusetts business trust.

Item 2(d) Title of Class of Securities:

          Common Stock

Item 2(e) CUSIP Number:

          63935N107

Item 3    Type of Person:

          (d)  Acorn is an Investment Company under section 8 of the Investment
               Company Act.

          (e)  WAM is an Investment Adviser registered under section 203 of the
               Investment Advisers Act of 1940; WAM GP is the General Partner of
               the Investment Adviser.

                               Page 5 of 10 Pages



Item 4    Ownership (at December 31, 2003):

          (a)  Amount owned "beneficially" within the meaning of rule 13d-3:

               1,861,000

          (b)  Percent of class:

               4.2% (based on 44,700,000 shares outstanding as of November 12,
               2003).

          (c)  Number of shares as to which such person has:

               (i)  sole power to vote or to direct the vote: none

               (ii) shared power to vote or to direct the vote: 1,861,000

               (iii) sole power to dispose or to direct the disposition of: none

               (iv) shared power to dispose or to direct disposition of:
                    1,861,000

Item 5    Ownership of Five Percent or Less of a Class:

          If this statement is being filed to report the fact that as of the
          date hereof the reporting person has ceased to be the beneficial owner
          of more than five percent of the class of securities, check the
          following: [X]

Item 6    Ownership of More than Five Percent on Behalf of Another Person:

          Not Applicable

Item 7    Identification and Classification of the Subsidiary Which Acquired the
          Security Being Reported on by the Parent Holding Company:

          Not Applicable

Item 8    Identification and Classification of Members of the Group:

          Not Applicable

Item 9    Notice of Dissolution of Group:

          Not Applicable

                               Page 6 of 10 Pages



Item 10   Certification:

               By signing below I certify that, to the best of my knowledge and
          belief, the securities referred to above were acquired and are held in
          the ordinary course of business and were not acquired and are not held
          for the purpose of or with the effect of changing or influencing the
          control of the issuer of the securities and were not acquired and are
          not held in connection with or as a participant in any transaction
          having that purpose or effect.

                               Page 7 of 10 Pages



                                    Signature

     After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.

Date:  February 10, 2004

          The undersigned corporation, on the date above written, agrees and
          consents to the joint filing on its behalf of this Schedule 13G in
          connection with its beneficial ownership of the security reported
          herein.

                                  WAM Acquisition GP, Inc.
                                     for itself and as general partner of
                                     COLUMBIA WANGER ASSET MANAGEMENT, L.P.


                                  By: /s/ Bruce H. Lauer
                                      ------------------------------------------
                                          Bruce H. Lauer
                                          Senior Vice President and Secretary

          The undersigned trust, on the date above written, agrees and consents
          to the joint filing on its behalf of this Schedule 13G in connection
          with its beneficial ownership of the security reported herein.

                                  COLUMBIA ACORN TRUST


                                  By: /s/ Bruce H. Lauer
                                      ------------------------------------------
                                          Bruce H. Lauer
                                          Vice President, Treasurer and
                                          Secretary

                               Page 8 of 10 Pages



                                  Exhibit Index

Exhibit 1   Joint Filing Agreement dated as of February 10, 2004 by and among
            Columbia Wanger Asset Management, L.P., WAM Acquisition GP, Inc. and
            Columbia Acorn Trust.

                               Page 9 of 10 Pages



                                                                       EXHIBIT 1

                       JOINT FILING AGREEMENT

     The undersigned hereby agree to the joint filing of the Schedule 13G to
which this Agreement is attached.

Dated: February 10, 2004

                                  WAM Acquisition GP, Inc.
                                      for itself and as general partner of
                                      COLUMBIA WANGER ASSET MANAGEMENT, L.P.


                                  By: /s/ Bruce H. Lauer
                                      ------------------------------------------
                                          Bruce H. Lauer
                                          Senior Vice President and Secretary


                                  COLUMBIA ACORN TRUST


                                  By: /s/ Bruce H. Lauer
                                      ------------------------------------------
                                          Bruce H. Lauer
                                          Vice President, Treasurer and
                                          Secretary

                               Page 10 of 10 Pages