He began his own production company, Harry Ackerman Prods, where he immediately signed an exclusive deal with Paramount TV to create TV series, specials and feature films on a co-production basis. He also went to work on network development for Hanna-Barbera Prods. He then joined Screen Gems, which later became Columbia Pictures Television, where he worked for 15 years, from 1958 until 1973. He worked on many TV shows while there, including, "Father Knows Best", "Bachelor Father" (for Universal), "Leave It to Beaver" (for Universal), "Dennis the Menace", "The Donna Reed Show", "Hazel", "Grindl", "Gidget", "Bewitched", "I Dream of Jeannie", "The Flying Nun", "The Monkees", and "The Partridge Family".