This paper examines the moral responsibilities of physicians, toward themselves and their colleagues, their students and patients, and society, in terms of the nature and exercise of professional self-regulation. Some of the author's close encounters with cases involving research misconduct, behavioral impairment or deviance, and medical practice at the moral margin, are described to illustrate why, in Freidson's words, physicians are a delinquent community with respect to the ways they meet their responsibility to govern the competence and conduct of their (...) members. (shrink)