The issue of social inequalities in health has become politically salient during the 1990s in many European countries. Research evidence and ideas that eventually came to the attention of national policy makers helped to trigger this change. The pathways of this information flow are traced through an examination of the work of international agencies and a presentation of case studies from three countries: the Netherlands, Britain, and Sweden. Each country's experience was different but nevertheless influenced and reinforced the courses of action adopted by the others. It is clear that, in order to meet the challenge that health inequalities pose to public health and policy, cooperation will become even more important in the future.