We investigate the dynamic relationship between residential choices of individuals and resulting long-term aggregate segregation patterns, allowing for feedback effects of macrolevel neighborhood conditions on residential choices. We reinterpret past survey data on whites' attitudes about desired neighborhoods as revealing large heterogeneity in whites' tolerance of black neighbors. Through agent-based modeling, we improve on a previous model of residential racial segregation by introducing individual-level heterogeneity in racial tolerance. Our model predicts, in the long run, a lower level of residential racial segregation than would be true with homogeneous racial tolerance. Further analysis shows that whites' tolerance of black neighbors is closely associated with their overall racial attitudes toward blacks.