Mark began his professional career in Los Angeles in 1983, securing his first job as the "Starter" in the film "Hot Dog...the Movie". He went on to land numerous Co-Star and Guest roles on episodic TV shows such as "Murder She Wrote", "Dynasty", "Knots Landing", "Who's the Boss", "LA Law", "Full House", "Seventh Heaven", "ER", "N.Y.P.D. Blue", "The West Wing", and "Criminal Minds". Mark also had recurring roles on TV shows like "Bay City Blues", "JAG", and "First Monday". In 1990, he secured a three-year contract on the FOX youth-oriented drama "Tribes". Mark established himself as a prominent figure in the Los Angeles theatre scene, winning Best Actor in a Feature Role from Stage Scene LA for his performances in "Finding Fossils" and "John is a Father" at The Road Theatre, as well as "Mom's Dead" at Sacred Fools. He appeared alongside Susan Sullivan and David Selby in Edward Albee's "A Delicate Balance" at the Odyssey Theatre, which won the LA Drama Critics Circle McCulloh Award for Best Revival.
