Boards of directors

It's no wonder this select group of CEOs is one of the most influential lobbying groups in Washington -- its members contribute a majority of all corporate income taxes paid to the federal government. At the seat of political power, the 38-year-old organization, which now represents 168 companies (128 of which are on the Fortune 500 list), helped kill the White House's push to tax overseas profits and the public-option component of health-care reform.

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