Jack Body composed ensemble, vocal, orchestral and electroacoustic music, as well as film music, music-theatre and image/sound installations. He was commissioned and performed by the New Zealand Symphony Orchestra, the Auckland Philharmonia, the New Zealand String Quartet and NZTrio, as well as international ensembles such as the Amsterdam Atlas Ensemble, the BBC Scottish Symphony Orchestra, the Song Company (Sydney), and Kronos Quartet, for whom he had written four works. He curated three Asia Pacific Festivals (1984, 1982, 2007), as well as festivals of New Zealand music in Amsterdam, Santa Cruz California, and Beijing, and published many scores and recordings of New Zealand music, as editor of Waiteata Music Press.

Jack Body documented traditional Indonesian music, and as manager of a Javanese gamelan he facilitated the creation of new repertoire for gamelan and other instruments, collaborating with numerous New Zealand composers as well as leading Indonesian artists. Other collaborative cross-cultural projects include O Cambodia, a programme with three other composers to create new works for piano trio and three traditional Cambodian musicians, and a project of new compositions played by the NZ String Quartet with the Forbidden City Chamber Orchestra (Beijing). His Songs and Dances of Desire, a tribute to the iconic New Zealand Maori drag queen Carmen Rupe, was a highlight of the 2013 Auckland Festival. He lectured in the School of Music at Victoria University of Wellington (now the NZ School of Music) from 1980 until his retirement from teaching in 2009. Jack Body died on 10 May 2015.