In House M.D., which character was played by Robert Sean Leonard?

In House M.D., Robert Sean Leonard played Dr. James Wilson.

Wilson is the head of the Department of Oncology at Princeton-Plainsboro Teaching Hospital and Dr. Gregory House’s closest friend. His specialty places him in a different department from House, whose team investigates unusual diagnostic cases.

The character is known for balancing House’s abrasive personality with a more empathetic approach to patients and colleagues. Wilson also serves as one of the show’s recurring moral counterweights, although he sometimes becomes involved in House’s risky decisions.

Robert Sean Leonard was already known for stage and screen work before joining the series. A common mix-up is confusing Wilson with Dr. James Wilson’s actor, since the character’s surname is often used on its own in the show. Wilson’s personal and professional relationship with House remains central throughout the series.