In L.A. in the '50s Young played jazz saxophone, leading a group with Billy Higgins, Dennis Budimir and Don Cherry. He also played with Eric Dolphy, Ornette Coleman, Terry Jennings, Don Friedman and Tiger Echols. At Yoko Ono's studio in 1960 he was director of the first New York loft concert series. He was the editor of An Anthology (NY 1963), which with his
Compositions 1960 became a primary influence on concept art and the Fluxus movement. In 1962 Young founded his group, The Theatre of Eternal Music, and embarked on The Tortoise, His Dreams and Journeys
(1964- ), a large work involving improvisation within strict predetermined guidelines. Young played sopranino saxophone and sang with the group. Dennis Johnson, Terry Riley, Angus MacLise, Marian Zazeela, Tony Conrad, John Cale, Jon Gibson, Jon Hassell, Lee Konitz and David Rosenboom are among those who worked in this group under Young's direction.

With Marian Zazeela in the early '60s he formulated the concept of a
Dream House, a permanent space with sound and light environments in which a work would be played continuously. Young and Zazeela have presented works in sound and light worldwide, from music and light box sculptures to large-scale environmental installations, culminating in two Dia Art Foundation realizations: the 6-year continuous 6-story Harrison Street
Dream House (NYC 1979-85) and the 1-year environment (22nd Street NYC 1989-90) within which Young presented The Lower Map of The Eleven's Division in The Romantic Symmetry (over a 60 cycle base) in Prime Time from 112 to 144 with 119 with the Theatre of Eternal Music Big Band. This 23-piece chamber orchestra was the largest Theatre of Eternal Music ensemble to appear in concert to date. Young has since presented Dream House sound environments at MAC Lyon (1999); Espace Donguy, Paris (1990); Ruine der K?nste, Berlin (1992); Pompidou Center, Paris (1994-95); Mus?e Art Contemporain Lyon (1999) and the MELA Foundation Dream House: Seven+Eight Years of Sound and Light, which opened at MELA Foundation, New York in 1993 and will be on view through 2008. As the first western disciple of renowned master vocalist Pandit Pran Nath, Young has performed and taught the Kirana style of Indian classical music since 1970.

The 1974 Rome live world premiere of Young's magnum opus The Well-Tuned Piano (1964-73-81-present), was celebrated by a commission for him to sign the B?sendorfer piano, which remains permanently in the special tuning. Gramavision's full-length recording of the continuously evolving 5-hour-plus work has been acclaimed by critics to be "the most important and beautiful new work recorded in the 1980s," "one of the great monuments of modern culture" and "the most important piano music composed by an American since the Concord Sonata." At the 1987 MELA Foundation La Monte Young 30-Year Retrospective he played the work for a continuous 6 hours and 24 minutes.

In the ‘80s and ‘90s, The Theatre of Eternal Music Brass and String Ensembles led by Ben Neill and Charles Curtis presented numerous performances in the U.S. and Europe of The Melodic Versions (1984) of The Four Dreams of China (1962), one of Young’s most important early minimal works, from which in 1991 Gramavision released a CD of The Second Dream of The High-Tension Line Stepdown Transformer. In 1990 Young formed The Forever Bad Blues Band, which has performed extensively in Germany, Austria, Holland, Italy and the U.S., presenting two to three-hour continuous concerts of Young's Dorian Blues, with Young, keyboard, Jon Catler, just intonation and fretless guitar, Brad Catler, bass, Jonathan Kane, drums, and Marian Zazeela, light design. In 1993 Gramavision released the 2-CD set, La Monte Young, The Forever Bad Blues Band, Just Stompin/Live at the Kitchen.

For La Beaute, the celebration of the Year 2000, the French government invited Young and Zazeela to create a four-month, continuous large-scale Dream House in a church in Avignon. L’Express L’An 2000 Supplement headlined their appraisal of the project: "La Monte Young: Le Son du Siecle."