Who portrayed Dr. James Wilson, Gregory House's closest friend, in House M.D.?

Robert Sean Leonard portrayed Dr. James Wilson, Gregory House's closest friend, in House M.D. Wilson is an oncologist and the head of the hospital's Department of Oncology for much of the series.

Wilson serves as a contrast to House. He is generally more empathetic and socially conventional, yet he repeatedly supports House despite the damage House's decisions can cause. Their friendship is one of the show's central long-running relationships.

Leonard was already known for film and stage work before House M.D. His earlier credits included the film Dead Poets Society, in which he played Neil Perry, and he later continued working in theatre and television.

The character's profession can cause another mix-up: Wilson is an oncologist, while Lisa Cuddy is the hospital administrator and Eric Foreman, played by Omar Epps, is a neurologist. Robert Sean Leonard is the actor associated with Wilson.