Princeton University has mandated proctoring for in-person exams, ending a 133-year tradition of unproctored exams based on an honor system. The decision was made in response to increasing concerns about academic integrity and the use of AI tools to cheat. The new policy requires instructors to be present in exam rooms as witnesses, but not to interfere with students. Proctors will document any suspected Honor Code violations and submit reports to the student-run Honor Committee.