Mantler has been among the few jazz musicians active in the compositional, performing, and business ends of music. He studied at Berklee in Boston before relocating to New York in 1964. After playing with Cecil Taylor's group, Mantler was part of the group that formed the Jazz Composer's Guild to allow experimental musicians better opportunities. The Guild didn't last, but they were the forerunner of the Jazz Composers Orchestra Association (JCOA), which Mantler formed as a nonprofit cooperative to commission, perform, and record new compositions for jazz orchestras in the late '60s. Mantler and composer Carla Bley have had a long and fruitful relationship since the '60s. He and Bley formed Watt Works Records in 1973. ~ Ron Wynn