From 2010 to 2030 the United States will become more racially and ethnically diverse, but demographic projections suggest the patterns of increasing diversity will vary widely across cities and regions. We project changes in the population shares across geographies for four major groups: Hispanics, non-Hispanic blacks, non-Hispanic whites, and non-Hispanic others. Though growing diversity across the United States will be welcome in many ways, it will also bring challenges to areas in which different groups increase in population share.