Aetna Inc. (NYSE: AET) is the third largest diversified healthcare provider, serving 35.3 million people in the United States and earning $34.2 billion in 2010 revenues.^{[1] [2]} Aetna sells a wide range of health and life insurance products categorized as health, dental, pharmacy, group life, disability, and long-term care. Aetna essentially sells protection from risk: as an insurer, is agrees to pay for a percentage of its customers' medical expenses in exchange for a fee, called the premium. The basic business plan is to offer clients a premium based on the the expected cost of caring for them, plus a markup for administrative costs and profit. Aetna's greatest challenge has been to maintain a profitable membership in light of increasing unemployment and U.S. health care reform.^[3]

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