Debates about the importance of race and class in shaping racial inequality involve theoretical models that focus on urban transformations and urban poverty and make predictions about the geographic distribution of social groups and social goods within the urban landscape. They state that inner city Blacks were geographically separated from important social and economic resources in the second half of the 20th century. Knowing that a metropolitan area has extremely high levels of segregation does not tell researchers anything about which inner city and suburban neighborhoods are minority neighborhoods. It does not provide researchers with any information about the spatial relationship between minority neighborhoods, White neighborhoods, and specific social goods. Demographic data for the Detroit metropolitan area were obtained from the 1970, 1980, and 1990 United States Censuses. Facility data were drawn from Michigan manufacturer directories of the same years. Results show that income-based environmental inequality was relatively strong in 1990 and environmental racial inequality in the Detroit metropolitan areas declined significantly from 1970 to 1990. The use of GIS allows for the merging of spatial and non-spatial data, the creation of maps that compare the distributions of social groups vis-à-vis important social goods, and the construction of spatially precise proximity indicators that are methodologically superior to those typically used by sociologists. Taking spatial measurement, spatial relationships, and geography seriously can have a significant impact on empirical results. 2 figures, 2 tables, 9 notes, 29 references