There is considerable concern and much evidence resident fatigue results in medical errors, some of which have serious consequences. Similarly, fatigue causes poor health in house-staff and places these individuals at greater risk for personal injuries, including motor vehicle accidents. These circumstances led the Accreditation Council on Graduate Medical Education to develop and, on July 1, 2003, to implement guidelines for all residency training programs limiting the time of in-house duty to 80 hours per week. Surveys of orthopaedic residents by the American Academy of Orthopaedic Surgeons, before and right after implementation of these new duty rules, confirm housestaff were working longer than 80 hours before July 2003 and are largely in compliance since that date. Residents generally approve of these changes and are personally happier, but also express concern for a loss of continuity of care and reduced exposure to operative cases. It remains to be demonstrated whether these new rules will improve patient care, enhance housestaff well-being, or influence education.