Which actor played Dr. James Wilson, Gregory House’s best friend, in House M.D.?

Robert Sean Leonard played Dr. James Wilson in House M.D. Wilson is an oncologist and one of the few people willing to maintain a close friendship with Gregory House despite House’s difficult behavior.

The character’s medical specialty is important to the series because Wilson frequently encounters patients with cancer-related complications, while also serving as a trusted sounding board for House’s diagnostic theories. Their friendship often supplies the show’s emotional counterpoint to House’s cynicism and social isolation.

Leonard was already known for film and stage work before joining the medical drama. His earlier credits included the film Dead Poets Society, in which he played Neil Perry, and substantial theater work. House M.D. gave him a long-running television role across all eight seasons.

Wilson is not one of House’s original diagnostic fellows. That distinction belongs to the first team assembled under House, while Wilson works in oncology and interacts with the team as a colleague, friend, and occasional consultant.