Because practicing physicians are poorly prepared to resolve many ethical issues that arise in patient care, this article proposes that residencies include practical training in medical ethics. Training in medical ethics helps physicians recognize ethical issues in patient care and resolve those issues wisely. Furthermore, such training has its maximum impact during the professionally formative years of residency. The article specifies key ethical concepts residents should know, including knowing how to obtain informed consent, knowing what to do about incompetent patients, knowing when to withhold or disclose clinical information, and knowing how to use resources properly. The article also points out that the success of residency training in ethics depends on strong commitments from the department: endorsement by the chairman and the residency program director; recruitment of several dedicated faculty; support for adequate ethics training for these faculty; dedication of conferences, rounds, and consultations to teaching ethics; and allocation of sufficient funds.