[3][4][5] After the Mintz Studio collapsed, he worked for Disney, mainly for war-time cartoons, such as Victory Through Air Power and Reason and Emotion.
After World War II was over, he went to Warner Brothers from 1948 to 1964, where he animated Merrie Melodies shorts starring Bugs Bunny, Porky Pig, and others, like What's Opera Doc, Tweet Tweet Tweety, and Hot Cross Bunny.
[8] After the Warner Bros. Cartoons studio shut down in 1963, he went to DePatie-Freleng Enterprises (for 10 years, 1963–1973) and produced The Pink Panther Show, Doctor Dolittle, and Dr. Seuss specials like The Lorax and The Cat in The Hat.
He was widely respected in the animation industry for his friendly personality plus his drafting, management and writing skills.
[4][7] After Fritz the Cat, he worked at Hanna-Barbera from 1974 to 1989 (15 years), and even started an animation college for the younger employees in 1976, eventually retiring in 1989.