Medicine, law, and social values are not static. Reexamining the ethical tenets of medicine and their application in new circumstances is a necessary exercise. The sixth edition of the American College of Physicians (ACP) Ethics Manual covers emerging issues in medical ethics and revisits older ones that are still very pertinent. It reflects on many of the ethical tensions in medicine and attempts to shed light on how existing principles extend to emerging concerns. In addition, by reiterating ethical principles that have provided guidance in resolving past ethical problems, the Manual may help physicians avert future problems. The Manual is not a substitute for the experience and integrity of individual physicians, but it may serve as a reminder of the shared duties of the medical profession.