This paper examines the role played by illicit drugs, especially marijuana and heroin, in the historic development and evolution of Jazz in the United States during the twentieth century. In addition to an assessment of the extent of drug use and kinds of drugs used by Jazz musicians and singers, the impact and costs of drug use on the lives of people in Jazz, and the changing patterns of drug use during several eras of Jazz production, the paper contextualizes drug use among Jazz performers and societal response to it in light of prevailing ethnic inequalities and critical medical anthropological theory.