Rising health care expenditures have led to numerous cost-control proposals. An examination of the ethical questions surrounding the role that physicians play in the control of health care costs suggests that unilateral rationing decisions by individual physicians at the bedside are morally unacceptable. Such decisions are arbitrary, ineffective in redistributing health care resources, and formally unjust. Restrictive gatekeeping (the creation of financial incentives for physicians to limit care given to individual patients) also seems unacceptable because of its morally significant effects. First, it disguises the role of those actually responsible for cost-control decisions; second, it routinely creates a "moral stress test" by forcing physicians to act in ways that are contrary to their own interests in order to serve the needs of patients; third, it undermines the trust between doctor and patient; and fourth, it rations by class of persons rather than class of technology. In contrast, a morally sound system would attempt to control costs by honestly informing patients and assigning responsibility justly, would encourage physicians to act in the interests of patients, would foster trust, and would recognize the great importance of equal treatment for all patients. Such a system would depend on input from an informed public and would apply equally to all members of society.