Medicine is, increasingly, a politicized profession. Physicians come to politics both as clinicians with expertise in health care delivery and as an interest group, looking to protect their economic self-interest in a highly regulated field. The political orientation and engagement of physicians are particularly important as the US navigates through a period of change and uncertainty in health care. This special issue sheds light on how physicians, both as individual citizens and as organized interest groups, navigate politics and influence core issues. As physicians organize and advocate, and as they counsel patients in their offices on politically impinged personal health issues, social scientists are investigating how they affect politics and how politics affects them.