On May 24-25, 2005 in Ann Arbor, Michigan, the US Environmental Protection Agency, the National Institute of Environmental Health Sciences, and the University of Michigan sponsored a technical workshop on the topic of connecting social and environmental factors to measure and track environmental health disparities. The workshop was designed to develop a transdisciplinary scientific foundation for exploring the conceptual issues, data needs, and policy applications associated with social and environmental factors used to measure and track racial, ethnic, and class disparities in environmental health. Papers, presentations, and discussions focused on the use of multilevel analysis to study environmental health disparities, the development of an organizing framework for evaluating health disparities, the development of indicators, and the generation of community-based participatory approaches for indicator development and use. Group exercises were conducted to identify preliminary lists of priority health outcomes and potential indicators and to discuss policy implications and next steps. Three critical issues that stem from the workshop were: (a) stronger funding support is needed for community-based participatory research in environmental health disparities, (b) race/ethnicity and socioeconomic position need to be included in environmental health surveillance and research, and (c) models to elucidate the interrelations between social, physical, and built environments should continue to be developed and empirically tested.