William Philip (Phil) Gramm (born July 8, 1942 in Fort Benning, Georgia) served as a Democratic Congressman (1978-1983), a Republican Congressman (1983-1984), and a Republican Senator from Texas (1985-2000).

In 1967, he received a Ph.D in economics from the University of Georgia. After receiving his Ph.D., Gramm taught economics for twelve years at Texas A&M University (1967-1978). In addition to his teaching Gramm worked as a partner at Partner, Gramm & Associates (1971-78).

In 1978, Gramm successfully ran as a Democrat for a seat in the United States House of Representatives. He kept his seat until the Democratic Party leadership in the House stripped him of his House Budget Committee position because of his outspoken support for President Ronald Reagan's economic policies. In response to this, Gramm decided to join the Republican Party.

Unlike other officials who have switched parties, Gramm resigned from Congress in 1983 and ran in a special off-year election for the same seat as a Republican. His rationale was that those who voted for him as a Democrat in 1982 may not have supported him as a Republican.

He served on the Budget Committee from the 101st Congress until leaving office in 2003. Gramm, Sen. Ernest F. Hollings, and former Sen. Warren Rudman devised a means of cutting the budget through indiscriminate, across-the-board spending cuts if deficit-reduction targets were not met. The resulting law that bears their names has largely been superseded by other budget-controlling mechanisms.

He ran for the Republican Party nomination in the 1996 presidential election.

Late in his senate career, he spearheaded efforts on banking reform laws.

Phil Gramm is married to Dr. Wendy Lee Gramm.