In the daily practice of pulmonary and critical care medicine, termination of life support is a common issue. During the past decade, withholding and withdrawing life support has increased remarkably among pulmonary and critical care physicians. Many patients are admitted to the intensive care unit even though they are part of a population with a high mortality rate. The goal of the health care team is to decide whether to try saving the patient who may live or to help the dying patient die with peace and dignity. Four principles of biomedical ethics play a role in end-of-life decision making: beneficence, nonmaleficence, autonomy, and justice. In addition, physicians must possess certain virtues to provide outstanding health care: benevolence, compassion, respect for humanity, prudence, truthfulness, and trustworthiness. During the past 2 decades, numerous court cases have helped to shape the practice of medicine concerning withholding and withdrawing life support. This article reviews the ethical decision making related to withholding and withdrawing basic and advanced life support and the issues dealing with advance directives and euthanasia.