ABSTRACT: This study examines patterns of ethnic residential integration in Great Britain and the United States. Using data from 2000/2001 censuses from these two countries, we compute segregation indexes for comparably defined ethnic groups by nativity and for specific foreign-born groups. We find that blacks are much less segregated in Great Britain than in the United States, and black segregation patterns by nativity tend to be consistent with spatial assimilation in the former country (the foreign-born are more segregated than the native-born) but not in the latter. Among Asian groups, however, segregation tends to be lower in the United States, and segregation patterns by nativity are more consistent with spatial assimilation in the United States but not in Great Britain. These findings suggest that intergenerational minority disadvantage persists among blacks in the United States and among Asians in Great Britain. We caution, however, that there are important differences in levels of segregation among specific foreign-born Asian groups, suggesting that assimilation trajectories likely differ by country of origin. Finally, the fact that segregation levels are considerably higher in the United States for a majority of groups, including white foreign-born groups, suggests that factors not solely related to race or physical appearance drive higher levels of ethnic residential segregation in the United States.