Patrick Gleeson (born November 9, 1934) is an American musician, synthesizer pioneer, composer, and producer.

Gleeson moved to San Francisco in the 1960s to teach in the English Department at San Francisco State. Gleeson began experimenting with electronic music in the mid-’60s at the San Francisco Tape Music Center using a Buchla synth and other devices. He resigned his teaching position to become a full-time musician. In 1968, “upon hearing Wendy Carlos‘ Switched-On Bach“, he bought a Moog synthesizer and opened the Different Fur recording studio in San Francisco.

He worked with Herbie Hancock in the early 1970s on two albums (Crossings and Sextant) and subsequent tours, pioneering synthesizers as a live instrument. Hancock initially hired Gleeson as a synthesizer technician and instructor, but ended up asking him to become a full-time band member, expanding the ensemble from six to seven musicians. Hancock has credited Gleeson with introducing him to synthesizers and teaching him technique. Sextant and Headhunters were both recorded in part at Different Fur studios. Gleeson has subsequently worked with many other Jazz musicians, including Lenny White, Freddie Hubbard, Charles Earland, Eddie Henderson and Joe Henderson.