The numerous challenges now facing the profession of medicine have led to an intense focus on professionalism by individual physicians and by their professional and academic organizations. In 2002, a distinguished group of leaders in internal medicine created the Physician Charter, which calls on physicians to reaffirm medical professionalism through commitment to three principles and 10 responsibilities. The Charter reflects a duty-based ethic that is chiefly concerned with physician competence. This article offers a critical analysis of the Physician Charter from the perspective of the traditional values of medicine as articulated in medical oaths and championed by leaders of past generations, exemplified by William Osler. The authors argue that medical professionalism should reflect the values of a virtue-based ethic that stresses compassion and beneficence, rather than the values of a duty-based ethic. The challenges that now confront the practice of medicine can be addressed successfully only to the extent that physicians promote virtue-ethics, act collectively in the public interest, and render service that clearly transcends their own self-interests.