Harman began work with Walt Disney in 1922 on the Laugh-O-Gram shorts. Harman and his partner, Rudolf Ising then rejoined Disney for the Oswald cartoons, but stayed with producer Charles Mintz after Disney was let go. Harman joined Warner Bros., but left in 1933 for MGM where he and Ising found success with the "Happy Harmonies" before being eclipsed by the animators of the time: William Hanna & Joseph Barbera--whom they hired.