Many family medicine educators have called for changing the family practice residency curriculum from a series of block rotations to a longitudinal curriculum. A longitudinal curriculum is one in which residents are based in the family practice center every day or nearly every day of all 3 years of their residency training. Residents learn most of the clinical content offamily medicine through experiences with patients from their continuity clinics, under supervision of family medicine faculty, rather than through specialty-specific block rotations supervised by specialists. An important purported benefit of longitudinal training is improved continuity of care between residents and their patients. Unfortunately, definitions of longitudinal training vary widely, and at least one study shows that supposedly longitudinal curricula do not result in better continuity of care. Further, there is some evidence that acquisition of knowledge by residents may be better with intensive block rotations than with longitudinal training. Thus, the supposed benefits of longitudinal residency training remain unproven.