William Michael Daley (born 1948) served as U.S. Secretary of Commerce and is a business executive.

William Daley was born in Chicago, Illinois, in 1948, graduating with a B.A. from Loyola University Chicago, and an LL.B. from John Marshall Law School. Except for a period from 1977 to 1980, during which time he sat on the Advisory Council of Economic Opportunity, Daley practiced law privately with the firm Daley and George.

He became associated with Amalgamated Bank of Chicago, where he was first vice chairman (1989-1990) and then president and chief operating officer (1990-1993). Daley returned to the practice of law, becoming a partner with the firm Mayer, Brown & Platt, from 1993 to 1997. In 1993, he served as special counsel to the President on issues relating to the passage of the North American Free Trade Agreement (NAFTA). In 1997, Daley became Secretary of Commerce in the second administration of President Bill Clinton, and he remained at that post until July, 2000, when he became chairman of Vice President Al Gore's presidential campaign, where he was in charge of choosing a vice presidential nominee.

In December of 2001, he was appointed President of SBC Communications Inc. to help reform the company's image. In May of 2004, Daley was made Midwest Chairman of J.P. Morgan Chase and Bank One Corp. to oversee post-merger operations from Chicago.

Daley currently serves on the Boards of Directors of Merck & Co., Inc, Boston Properties, Inc., and Loyola University Chicago. He also sits on the Council on Foreign Relations.

He is the son of the late Chicago Mayor Richard J. Daley and the brother of the city's current mayor, Richard M. Daley.