Sedation is a clinically important therapeutic intervention in the imminently dying patient. As the patient with an advanced, irreversible illness nears the end of life, symptoms accumulate that are progressively more difficult to manage and that may become refractory to standard medical interventions. The most common of these intractable symptoms are pain, agitated delirium, dyspnea, and existential or psychological distress. Various therapeutic options available for relieving these symptoms include physician-assisted suicide, euthanasia, acceptance of unrelieved suffering, and terminal sedation. Some commentators have voiced concerns that sedating the imminently dying patient inevitably hastens death, and that this practice, in fact, is a surrogate form of physician-assisted suicide or euthanasia. Ethical arguments invoked to support the use of terminal sedation include the principle of double effect, which draws a moral distinction between the intention of an act (in this case, to relieve suffering) and its foreseen but unintended consequence (premature death). This author views sedation as a necessary, although risk-laden, procedure that, if practiced by trained, dedicated clinicians, maintains the physician's twin obligations to benefit patients and to "do no harm."