This article explores theoretical and applied questions that are relevant to social scientists' efforts to understand and confront sexual stigma. A framework is presented for conceptualizing such stigma as a cultural phenomenon with structural and individual manifestations. The latter include enacted stigma and felt stigma, as well as internalized stigma, which encompasses self-stigma among sexual minorities and sexual prejudice among heterosexuals. Insights suggested by the model for reducing sexual prejudice are discussed. At the structural level, the framework highlights processes whereby heterosexism legitimates and perpetuates sexual stigma and the power differentials that it creates. Social and behavioral scientists, roles in working to eliminate heterosexism are discussed, and psychologists' contributions to court cases challenging state sodomy laws are described. It is argued that confronting sexual stigma will not only address an important social problem but will also enrich scientific understanding of human behavior.