Communities located near multiple sources of pollution, including current and former industrial sites, major roadways, and agricultural operations, are often predominantly low-income, with a large percentage of minorities and non-English speakers. These communities face additional challenges that can affect the health of their residents, including limited access to health care, a shortage of grocery stores, poor housing quality, and a lack of parks and open spaces. Research is now showing that environmental exposures can interact with social stressors, thereby worsening health outcomes. Age, nutrition, genetic characteristics, and preexisting health conditions also increase the risk of adverse health effects from exposure to pollutants. There are existing approaches for characterizing cumulative impacts, which vary in their analytical method and level of community engagement. Biomonitoring, health risk assessment, ecological risk assessment, health impact assessment, burden of disease, and cumulative impacts mapping have all been used to evaluate aspects of this issue. Although such approaches have merit, they each also have significant constraints. New developments in exposure monitoring, mapping, toxicology, and genomics, especially when informed by community participation, have the potential to advance the science on cumulative impacts and to improve prioritization, resource allocation, and risk reduction