This paper conceives of residential segregation as a multidimensional phenomenon varying along five distinct axes of measurement: evenness, exposure, concentration, centralization, and clustering. Twenty indices of segregation are surveyed and related conceptually to one of the five dimensions. Using data from a large set of U.S. metropolitan areas, the indices are intercorrelated and factor analyzed. Orthogonal and oblique rotations produce pattern matrices consistent with the postulated dimensional structure. Based on the factor analyses and other information, one index was chosen to represent each of the five dimensions, and these selections were confirmed with a principal components analysis. The paper recommends adopting these indices as standard indicators in future studies of segregation.