Many advocates of policy to implement the findings of research on the multiple determinants of health accord scant attention to the determinants of health policy in democratic countries. The principle determinants of the allocation of scarce resources to improving health include: the priorities of voters; the diffusion of responsibility for improving health; the absence of evidence about matters of consequence to policy makers; the arraying of some evidence in ways that frustrate policy making; resistance to addressing determinants other than clinical services and traditional public health practices among many professionals in these fields, as well as by industries that supply the health sector; and the special political influence of persons who suffer serious chronic disease and of members of their families.