This paper addresses the appropriate role for public input into priority setting for federal funding of biomedical research and development. The public should be involved in priority setting because researchers should be publicly accountable, because the public has a right to oversee government activities, and because public input is needed to assess normative questions related to the burden of disease and health care needs. On the other hand, political factors arising from public input can also hamper the governmentÕs ability to allocate funds according to the burden of disease or to promote the progress of biomedical science. When it comes to public input into R & D priority setting, more is not necessarily better. What is needed is the right balance of public and expert decision making with respect to the setting of biomedical R & D priorities.