The FDA recently approved Ceredase™, a new treatment for Gaucher's disease, under the provisions of the Orphan Drug Act. Ceredase™ is unusually expensive, but there are no satisfactory alternative therapies. It appears likely that Ceredase™would not have become available without the protection of the Orphan Drug Act, but its expense and the lack of information about its long-term effects on health raise questions about whether the ODA provides appropriate incentives to develop cost-effective technologies.