She was an episode director during the first season, then was Supervising Director for the rest of the show's run. She storyboarded and directed the episode Daria! and directed the two made-for-tv movies, "Is It Fall Yet?" and "Is It College Yet?".
She also worked on projects such as Ice Age: The Meltdown, Horton Hears a Who!, and Ice Age: Dawn of the Dinosaurs, where she provided the voice of Scratte.
Burnout Girl, one of the more popular background characters in the show, was modeled after Karen's appearance.