Throughout the early and mid-'70s, he played the part of studio musician and bassist, and formed two fusion projects, Happy End and Tin Pan Alley. Later in the '70s, he began recording tape and synthesizer experiments which culminated in the album Cochin Moon, released on the Japanese King Records. By 1978, his group Harry Hosono & the Yellow Magic Band had sprung into Yellow Magic Orchestra, with Ryuichi Sakamoto and Yukihiro Takahashi. Coming just a few years after electro futurists Kraftwerk and Tangerine Dream, YMO pursued a similar trail, later incorporating synth pop and new wave as well and becoming Japan's most successful band during the '80s -- even though they had broken up by 1984.

Even while Yellow Magic Orchestra was still around, Hosono had been busy with other projects. With three labels to his credit (YEN, Non-Standard, and Monad Music) and releases on those labels under guises such as S-F-X, Mercuric Dance, and -- most prolifically -- F.O.E. (Friends of the Earth), Haruomi Hosono stayed active into the late '80s. He composed scores for the films Paradise View and The Tales of Genji, but became disgusted with the industry and withdrew from music altogether by the turn of the decade. The pioneers of ambient house began to namecheck Yellow Magic Orchestra in the early '90s -- even producing a YMO remix album called High Tech/No Crime featuring the Orb plus many others -- and Hosono returned with 1992's Medicine Compilation From the Quiet Lodge. Albums for Creation and Polygram followed during the mid-'90s.