What department does Gregory House lead at Princeton-Plainsboro in House M.D.?

Gregory House leads the Department of Diagnostic Medicine at Princeton-Plainsboro in House M.D. The department handles difficult cases that remain unexplained after routine medical investigation.

House's team approaches patients as diagnostic puzzles, combining medical history, testing, observation, and differential diagnosis. This structure gives the series its distinctive medical-detective format and separates House's work from ordinary hospital treatment.

The department is fictional, although diagnostic medicine is a real clinical activity practiced across specialties. In real hospitals, complex diagnosis is usually collaborative and may involve internists, specialists, laboratory physicians, radiologists, and other professionals rather than a single department operating exactly like House's.

Viewers sometimes call House's unit an infectious-disease department because many cases involve infection. That is not its formal role. The defining function of the unit is diagnosing rare, complex, or unexplained conditions.