Bill Giles was a three-year letterwinner in tennis while at Denison. He graduated in 1956 with a degree in economics.
Giles served as business manager of the Nashville Vols, a minor league baseball team based out of Nashville, Tennessee, and spent three years as a navigator in the Air Force. He became the press agent for the Houston Colt .45s (now known as the Houston Astros) in 1962, and stayed there until he joined the Philadelphia Phillies organization.
Giles has been affiliated with the Phillies since 1969. He has been the owner of the club since 1981 when he purchased the team from the Carpenter family. Giles served as team president from 1982 to 1981 and was General Manager from 1984 to 1987. He has held the title of chairman since 1988.
Bill Giles is the son of former National League president Warren Giles.