The costs of prevention. A prevention program is cost-effective if it yields more health benefits than do alternative uses of health care resources. Some prevention programs meet this standard: either they actually save more health care resources than they utilize, or their net costs per healthy year of life gained are lower than those of alternatives such as curative or palliative medicine. Other prevention programs, however, are less cost-effective than are medical treatments for the same disease. One lesson for public policy is that generalizations about the cost-effectiveness of "prevention" are unwise. Another lesson is that prevention programs should not be subjected to a higher standard than other health programs: they should not be expected to save money, but they should be expected to yield improved health at a reasonable price. 