In this article, we examine the components of medical professionalism; identify the roots of the loss of professional autonomy by physicians in the United States--a process that, in effect, is leading to the deprofessionalization of American medicine; discuss why such deprofessionalization is undesirable for the society; and explore three health care delivery systems and their effects on deprofessionalization. We suggest that a system based on organizations set up and directed by physicians will be the system that best preserves medical professionalism and serves the public interest.