Infanticide, like most other species of homicide, is probably coeval with the human race itself. In modern Western civilization, what were formerly the most powerful incentives to infanticide have virtually disappeared. As with other social problems that affluence has seemed to solve, however, infanticide has reappeared in a new form that seems to have been made possible by affluence itself. This "new infanticide" occurs in a place whose very existence is the result of a tremendously wealthy society's devotion to its most vulnerable and least “useful” members. The modern neonatal intensive care unit, which treats, and often saves, extremely ill newborn children, who during most of history would surely have died, has proven to be a setting where many of the age-old incentives for infanticide have begun to operate again. The “new infanticide” consists of withholding food or needed medical treatment from selected infants who suffer from one or more serious, though treatable, medical problems. The national government has now enacted legislation designed to curtail the practice of infanticide by the medical profession. This paper traces the genesis of that legislation, explores the problem to which it is addressed, and evaluates its prospects for success.