After the Revue ended in 1976, Mansfield and two other members of Dylan's band, T-Bone Burnett and Steven Soles, formed The Alpha Band. The band released three albums, The Alpha Band in 1977, Spark In The Dark in 1977, and The Statue Makers of Hollywood in 1978.
Mansfield composed the music for the 1980 film Heaven's Gate — he appeared in the movie, playing the fiddle on roller skates — and has since gone on to write scores for a number of other films, including others directed by Heaven's Gate'sMichael Cimino. Mansfield cobbled together the soundtrack album for Songcatcher. He also composed the music for the soundtrack to The Ballad of Little Jo (1993), a movie written and directed by Maggie Greenwald, whom he married in 1993.