Carla Bley (born Lovella May Borg, May 11, 1936) is an American jazz composer, pianist, organist and bandleader. An important figure in the free jazz movement of the 1960s, she is perhaps best known for her jazz opera Escalator over the Hill (released as a triple LP set), as well as a book of compositions that have been performed by many other artists, including Gary Burton, Jimmy Giuffre, George Russell, Art Farmer, John Scofield and her ex-husband Paul Bley.

Bley was born in Oakland, California to Emil Borg (1899–1990), a piano teacher and church choirmaster, who encouraged her to sing and to learn to play the piano, and Arline Anderson (1907–1944), who died when Bley was eight years old. After giving up the church to immerse herself in roller skating at the age of fourteen, she moved to New York at seventeen and became a cigarette girl at Birdland, where she met jazz pianist Paul Bley.