The environment in which physicians practice and patients receive care continues to change. Increasing employment of physicians, changing practice models, new regulatory requirements, and market dynamics all affect medical practice; some changes may also place greater emphasis on the business of medicine. Fundamental ethical principles and professional values about the patient-physician relationship, the primacy of patient welfare over self-interest, and the role of medicine as a moral community and learned profession need to be applied to the changing environment, and physicians must consider the effect the practice environment has on their ethical and professional responsibilities. Recognizing that all health care delivery arrangements come with advantages, disadvantages, and salient questions for ethics and professionalism, this American College of Physicians policy paper examines the ethical implications of issues that are particularly relevant today, including incentives in the shift to value-based care, physician contract clauses that affect care, private equity ownership, clinical priority setting, and physician leadership. Physicians should take the lead in helping to ensure that relationships and practices are structured to explicitly recognize and support the commitments of the physician and the profession of medicine to patients and patient care.