There currently is a scarcity of scientific information to guide public policy decisions about issues of «environmental justice»; broadly defined as the goal of achieving adequate protection from the harmful effects of environmental agents for everyone, regardless of age, culture, ethnicity, gender, race, or socioeconomic status. This paper highlights several key methodological issues that need to be addressed as part of ongoing efforts to strengthen the scientific foundation for informed decision-making regarding environmental justice. Specifically, careful thought must be given to the selection of appropriate (1) statistical tests, (2) geographic unit(s) of analysis, (3) exposure estimators, and (4) comparison (reference) populations