The directory contains an extensive list of existing data sets that can be used to address these determinants. The data sets are organized according to 12 dimensions, or broad categories, of the social environment. Each dimension is subdivided into various components. This directory grew out of a project based at the University of Michigan School of Public Health and funded by the Centers for Disease Control and Prevention (CDC). Investigators from the United States and Europe were invited to a workshop to review an initial list of dimensions important for understanding social determinants of health. Participants represented a wide range of disciplines including epidemiology, sociology, geography, medicine, demography, economics, developmental psychology, education, and toxicology. Others with interests and expertise in the effects of community contextual characteristics on health were also invited, including government experts on data sources and geographic information systems, public health practitioners, and experts on community consultation and processes.