He was a member of Esoteric Circle, a quartet with guitarist Terje Rypdal, bassist Arild Anderson and drummer Jon Christensen that played a unique hybrid of jazz-rock, free jazz and progressive-rock on Esoteric Circle (october 1969), particularly the longer Rabalder, SAS 644 and Karin's Mode, on Afric Pepperbird (september 1970), with the twelve-minute Beast of Kommodo, Blow Away Zone and the catchy Afric Pepperbird, and on Sart (april 1971), that added pianist Bobo Stenson to the quartet and contained the 14-minute Sart, Song of Space and Irr. The ambience of these recordings was permeated by the zen-like quality of his long tones and pauses and by the folk-like quality of his melodies.

Garbarek also formed Popofoni, whose Popofoni (1973) documented a live 1970 performance, including a 25-minute Valse Triste and a 21-minute Arnold.

A trio with Anderson and Finnish percussionist Martii-Juhani "Edward" Vesala yielded the darker and more strident Triptykon (november 1972). After a collection of covers, Witchi-Tai-To (november 1973), notable only for a 20-minute version of Don Cherry's Desireless (Cherry's original was only one-minute long), and collaborations with Art Lande and Keith Jarrett, Garbarek entered a new phase of his career. Leaving behind both the rock and the free excesses of his classics, Garbarek employed a new quartet with Stenson, Christensen and bassist Palle Danielsson for Dansere (november 1975), a far less experimental and much more baroque work that defined the soothing "ECM sound" (particularly the 16-minute Dansere). The new format led to the drum-less Dis (december 1976), ostensibly a sax-guitar duo (Garbarek on tenor, soprano and wood flute, Ralph Towner on 12-string and classical guitars), whose Vandrere (with windharp), Skygger (with brass) and Dis (with windharp) basically transposed Brian Eno's ambient music into jazz music, one of the most influential ideas in the history of post-bop jazz. That idea got a bit out of control on the four lengthy tracks of Places (december 1977), including Reflections, Going Places and Passing, performed by a quartet with Garbarek on tenor, soprano and alto, guitarist Bill Connors, John Taylor on organ and piano, and drummer Jack DeJohnette, and on Photo With Blue Sky, White Cloud, Wires, Windows and a Red Roof (december 1978), featuring a quintet with Connors, Taylor, bassist Eberhard Weber and Christensen and containing White Cloud, The Picture, Red Roof.

Garbarek then embarked in an idiosyncratic exploration of world-music via Folk Songs (november 1979) and Magico (june 1979), two collaborations with bassist Charlie Haden and Brazilian guitarist Egberto Gismonti, Aftenland (december 1979), a (more adventurous) collaboration with Pipe organist Kjell Johnsen, Eventyr (december 1980), a collaboration with guitarist John Abercrombie and Brazilian percussionist Nana Vasconcelos devoted to Scandinavian melodies, Afro-Latin rhythms and Far-Eastern atmospheres (Soria Maria, Eventyr, Once Upon a Time, East of the Sun).

Garbarek returned to his ethereal brand of "ambient jazz" with Paths Prints (december 1981), featuring Garbarek on tenor and soprano, Bill Frisell on guitar, Weber and Christensen. Footprints represented the state of the art in coloring and breathing life into fragile melodies. The collaboration with Frisell and Weber continued on Wayfarer (march 1983), that contains Pendulum, whereas It's OK To Listen To The Gray Voice (december 1984), containing White Noise of Forgetfulness, replaced Frisell with the more robust guitar of David Torn and closed the guitar trilogy.

In the meantime Garbarek had recorded extensively with Keith Jarrett, Terje Rypdal, Ralph Towner and Ravi Shankar. He also scored (or, better, sculpted) music for film, tv and theater, mostly playing all instruments (including synthesizers) by himself. This solo art surfaced on six title-less pieces of All Those Born With Wings (august 1986), including a lengthy sax duet in the fifth piece, a flute-synth duet in the first, a droning third piece and a piano-sax duet in the fourth.

Garbarek adopted the electronic and melodic language of new-age music with Legend Of The Seven Dreams (july 1988), that featured electronic keyboards (Rainer Bruninghaus), bass (Weber) and percussion (Vasconcelos). Piano and synthesizer coexisted on I Took Up The Runes (august 1990), highlighted by the five-movement Molde Canticle.

The crisis continued via a series of erratic collaborations: Star (january 1991), with bassist Miroslav Vitous and drummer Peter Erskine, Atmos (february 1992), with Miroslav Vitous, Madar (august 1992), with Anouar Brahem on oud and Ustad Shaukat Hussain's tabla, Ragas and Sagas (may 1990), with Usted Fateh Ali Khan And Pakistani musicians, etc.

Now become a mainstream musician, Garbarek made the least original and least focused albums of his career. The return of the keyboards-based group, Twelve Moons (september 1992), mixed original, classical and ethnic material. Officium (september 1993) jumped on the bandwagon of the revival of Gregorian chants, fashionable at the time, a commercial feat repeated on Mnemosyne (april 1998). The return to his spare ambient-jazz sound, Visible World (june 1995), was monumental but rather uneventful (vocalist Mari Boine, electronic keyboardist Rainer Bruninghaus, bassist Eberhard Weber, French drummer Manu Katche, percussionist Trilok Gurtu, percussionist Marilyn Mazur). The double-CD Rites (march 1998), featuring electronic keyboardist Bugge Wesseltoft, Bruninghaus and Weber, focused on ceremonial atmospheres (and therefore thick percussion layers). In Praise Of Dreams (june 2003), featuring viola player Kim Kashkashian and drummer Manu Katche, further inhibited his smooth, facile, relaxing muzak.

Garbarek on soprano and tenor sax and his Hilliard Ensemble performed medieval sacred music on Officium Novum (july 2009), recorded in a monastery.

The live Remember Me My Dear (october 2014) reunited Jan Garbarek and the vocal Ensemble Hilliard Ensemble twenty years after Officium (september 1993).