Harry Colomby began his entertainment career as the manager for jazz musician Thelonious Monk and appeared in the documentary Thelonius Monk: Straight, No Chaser. Colomby wrote for several popular comedians in the late 1960s. He later worked as a story editor on ABC's television series spoof of Robin Hood, "When Things Were Rotten." Among his numerous other credits, he was co-creator and co-producer of the CBS series "Working Stiffs" in which Keaton starred early in his career.

Harry became Michael's manager in the late 1970s and eventually producing partner. Colomby served as the co-producer on Mr. Mom, and executive producer on Breakdown, Speechless, One Good Cop, Touch and Go, and Johnny Dangerously.