Harman and Ising first worked in animation in the early 1920s at Walt Disney's studio in Kansas City. When Disney moved operations to California, Harman, Ising, and fellow animator Carmen Maxwell stayed behind to try to start their own studio. Their plans went nowhere, however, and the men soon joined Disney out West to work on his Alice Comedies and Oswald the Lucky Rabbit films.
When Disney lost control of his Oswald character, Harman and Ising went to work for Charles Mintz, who now held the rights to Oswald. They still held ambitions of starting their own studio, however, and they created the cartoon "Bosko, the Talk-Ink Kid" in 1929. The sound cartoon impressed Leon Schlesinger, who paired Harman and Ising with Warner Bros. Schlesinger wanted the Bosko character to star in a new series of "talkie" cartoons he dubbed Looney Tunes. The two animated "Sinkin' in the Bathtub" in 1930, and the cartoon did well. Harman took over direction of the Looney Tunes starring the character, while Ising took a sister series called Merrie Melodies that consisted of one-shot stories and characters.
The two animators broke off ties with Schlesinger later in 1933 over budget disputes with the miserly producer. They had maintained the rights to the Bosko character, and they signed a deal with MGM to start a new series of Bosko shorts in 1934. The two maintained the same sort of workload they had had at Warner Bros.: Harman worked on Bosko shorts, and Ising directed one-shots. They also tried unsuccessfully to create new cartoon stars for their new distributors. Their cartoons, though technically superior to those they had made for Schlesinger, were still music-driven shorts with little to no plot. When the new Happy Harmonies series ran significantly over-budget in 1937, MGM fired Harman and Ising and established its own in-house studio headed by Fred Quimby.
Harman and Ising still found some work as animation freelancers, directing, for example, the Silly Symphony "Merbabies" for Disney in 1938. When Disney later reneged on a deal he had made for two other Harman-Ising pictures, the animators sold the cartoons to Quimby at MGM. Quimby later agreed to hire the animators back to the studio. Ising created the character Barney Bear for MGM at this time, basing the sleepy-eyed character partially on himself. In 1939, Harman created his masterpiece, "Peace on Earth", a downbeat morality tale about two squirrels discovering the evils of humanity, which was nominated for an Oscar. Despite the success of this and other cartoons, MGM's production under Harman and Ising remained low.
In 1941, Harman left MGM and started a new studio with Disney veteran Mel Shaw. The two took over Ub Iwerks' old studio in Beverly Hills, California, where they created training films for the Army. Ising also quit the studio to join the military.
Harman and Ising are little known, even among animation fans. This stems largely from the fact that they did not create any enduring characters. Instead, they created studios that would later produce such characters. Nevertheless, without them, the world might never have seen such famous characters as Bugs Bunny, Daffy Duck, and Tom and Jerry.