Mark was born the son of a frustrated actor who had taken on a career in advertising to pay the bills. All his life, mark was encouraged to participate in community theatre.
He entered Yale and declared himself a math major. Eventually, he switched majors to psychology. Finally, he earned a MFA in drama.
Mark has had many varied acting roles on the stage, in film, and on TV. He is best known for his role on the TV sit-com Perfect Strangers.