This review summarizes current knowledge about the social sources of differences in blood pressure between blacks and whites in the United States. Genetic variables may play some role in explaining black-white differences in blood pressure, but social factors are more important than genetic ones. I review evidence linking stress, social integration, coping styles, and health behavior (including obesity) to high blood pressure, emphasizing that the distribution of these risk factors is shaped by larger social structures and processes. Effective efforts to reduce stress and improve health practices must not focus only on the individual but must seek to alter the social, economic, and political structures and arrangements that produce disease.