The rule of rescue describes the moral impulse to save identifiable lives in immediate danger at any expense. Think of the extremes taken to rescue a small child who has fallen down a well, a woman pinned beneath the rubble of an earthquake, or a submarine crew trapped on the ocean floor. No effort is deemed too great. Yet should this same moral instinct to rescue, regardless of cost, be applied in the emergency room, the hospital, or the community clinic? In health care, the desire to save lives at any cost must be reconciled with the reality of resource scarcity. As one example, the estimated cost for prophylactic Factor VIII to treat one patient with hemophilia for one year is $300,000. Costs of this magnitude have been accepted by public and private insurers in the developed world, even though, in principle, these sums could provide greater overall health benefit if allocated to pay for the unmet health care needs of many other patients. Looking forward, however, broad application of the rule of rescue will be increasingly untenable. But the moral instinct will remain: the desire to help those weakest among us, especially when their small numbers allow us to see them as unique individuals. What, then, is the ethical framework that can guide coverage and reimbursement decisions for orphan drugs into the future?