Cosio worked on several cartoons for Filmation, Hanna-Barbera, Disney, Don Bluth, Warner Bros. Animation, and Crest Animation Productions. Cosio's other credentials include the 1969 series Hot Wheels, The Puppy Saves the Circus, The Chipmunk Adventure, FernGully: The Last Rainforest, The Thief and the Cobbler (as The Princess and the Cobbler), The Magic Paintbrush, and Asterix Conquers America. Most recently, Cosio animated for the Curious George film.