The environment can be thought of in terms of physical and social dimensions. The social environment includes the groups to which we belong, the neighborhoods in which we live, the organization of our workplaces, and the policies we create to order our lives. There have been recent reports in the literature that the social environment is associated with disease and mortality risks, independent of individual risk factors. These findings suggest that the social environment influences disease pathways. Yet much remains to be learned about the social environment, including how to understand, define, and measure it. The research that needs to be done could benefit from a long tradition in sociology and sociological research that has examined the urban environment, social areas, social disorganization, and social control. We summarize this sociological literature and discuss its relevance to epidemiologic research.