Kaitlin developed an interest in acting while studying theater at the University of Oregon in her home town Portland. She went to Los Angeles to try and make living as an actress and she got a role in the Sunday Company at the Ground Lings theater. Her appearances was not unnoticed and she soon found herself with reoccurring roles on the Drew Carey Show, Curb your Enthusiasm and Meet the Marks. After that Kaitlin has starred in several shows on FOX. As of 2005 she is starring in FX's comedy It's Always Sunny in Philadelphia.