Ethical dilemmas pervade modern geriatric medicine. What is considered right or wrong will differ depending on, among other things, the patient’s religion. The three Abrahamic monotheistic religions, Judaism, Christianity (its Catholic variant), and Islam all have carefully considered positions on medical ethics. Although much is held in common, there are significant differences. The authors present three clinical cases, each of which presents ethical dilemmas typical of geriatric care, especially at the end of life. On the basis of these scenarios, the normative ethical position of each religion is compared and contrasted. It is hoped that this approach will offer the geriatrician a useful approach to treating patients in an increasingly multicultural society. J Am Geriatr Soc 51:1149–1154, 2003.