Medicine, law, and social values are not static. Reexamining the ethical tenets of medical practice and their application in new circumstances is a necessary exercise. The fifth edition of the College's Ethics Manual covers emerging issues in medical ethics and revisits old ones. It reflects on many of the ethical tensions faced by internists and their patients 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 obligations and duties of the medical profession.