Brian Peter George St. John le Baptiste de la Salle Eno (born 15 May 1948), commonly shortened to Brian Eno and previously as simply Eno (pronounced /ˈiːnoʊ/), is an English musician, composer, record producer, music theorist, singer and visual artist, best known as one of the principal innovators of ambient music.

Eno studied at art school, taking inspiration from minimalist painting, but he had little musical education or playing experience when he joined the band Roxy Music as their keyboards and synthesizers player in the early 1970s. Roxy Music's success in the glam rock scene came quickly, but Eno soon tired of conflicts with lead singer Bryan Ferry, and of touring, and he left the group after the release of For Your Pleasure (1973), beginning his solo career with the art rock records Here Come the Warm Jets (1974) and Taking Tiger Mountain (By Strategy) (1974).

Eno extended his reach into more experimental musical styles with No Pussyfooting (1973) and Evening Star (1975), both collaborations with Robert Fripp, The Lamb Lies Down on Broadway (1974) by Genesis where his work is credited as "Enossification", and his influential solo records Another Green World (1975) and Discreet Music (1975). His pioneering ambient efforts at "sonic landscapes" began to consume more of his time beginning with Ambient 1/Music for Airports (1978) and later Apollo: Atmospheres and Soundtracks (1983) which was composed for the documentary film For All Mankind. Eno nevertheless continued to sing on some of his records, ranging from Before and After Science (1977) to Wrong Way Up (1990) with John Cale to most recently Another Day on Earth (2005).

Eno's solo work has been extremely influential, pioneering ambient and generative music, innovating production techniques, and emphasizing "theory over practice". He also introduced the concept of chance music to popular audiences partly through collaborations with other musicians. By the end of the 1970s, Eno had worked with David Bowie on the seminal "Berlin Trilogy," helped popularise the American punk rock band Devo and the punk-influenced "No Wave" genre, and worked frequently with Harold Budd, John Cale, Cluster, Robert Fripp and David Byrne, with whom he produced the influential My Life in the Bush of Ghosts (1981). He produced and performed on three albums by Talking Heads, including Remain in Light (1980); produced seven albums for U2, including The Joshua Tree (1987); and worked on records by James, Laurie Anderson, Coldplay, Depeche Mode, Paul Simon, Grace Jones and Slowdive, among others.

Eno pursues multimedia ventures in parallel to his music career, including art installations, a newspaper column in The Observer and a regular column on society and innovation in Prospect magazine, and "Oblique Strategies" (written with Peter Schmidt), a deck of cards in which each card has a cryptic remark or random insight meant to resolve a dilemma. He continues to collaborate with other musicians, produce records, release his own music, and write.