William Henry Donaldson was an American businessman who was the 27th Chairman of the U.S. Securities and Exchange Commission (SEC), serving from February 2003 to June 2005. He served as Under Secretary of State for International Security Affairs in the Nixon Administration, as a special adviser to Vice President Nelson Rockefeller, chairman and CEO of the New York Stock Exchange, and chairman, President and CEO of Aetna. Donaldson founded Donaldson, Lufkin & Jenrette.
