Mary Harrington was Invader Zim's executive producer. Along with Invader Zim, she has also produced Ni Hao, Kai-Lan, Hey Arnold!, The Angry Beavers, Aaahh!! Real Monsters, Adventures in Diapers, Rocko's Modern Life, Kablam! (Only in one episode), Doug, The Ren & Stimpy Show, Psyched for Snuppa, Dino-Riders in the Ice Age and Dino-Riders (Only in one episode).
She only has written for Ni Hao Kai-Lan so far. Additionally, she was the Production Manager in The Ren & Stimpy Show and Dino-Riders (Only in one episode). She was given special thanks in The Fairly OddParents (Only in one episode) and Kablam! (Only in one episode).