Robert Sean Leonard (born February 28, 1969, Westwood, New Jersey, U.S.) is an American actor who first gained recognition for his role as tragic student Neil Perry in the film, Dead Poet's Society.

In recent years, Leonard has achieved international recognition for his role as Dr. James Wilson in the American medical drama series House M.D.

He appeared in the Law & Order: Special Victims Unit episodes Perverted Justice, Transgender Bridge, and Catfishing Teacher as A.D.A. Kenneth O'Dwyer.