When studies are done of Hispanics, the results mostly reflect the experience of Mexicans who are more than 60% of the total. But observers would be mistaken if they thought they knew Hispanics in the U.S. by looking only at Mexicans. The differences among Hispanic groups are becoming more salient in three ways. First, non-Mexicans are growing fast and are now present in large numbers… Second, some groups are doing a lot better than Mexicans. Puerto Ricans and Cubans earn more, and Agentinas and Venezuelans earn much more… Third, these groups also have different levels and trends in separation from non-Hispanics. South Americans are less segregated than Mexicans, while Dominicans and Central Americans are much more segregated……This report summarizes what is known about the sizes, social backgrounds and locations of each major Hispanic group. We emphasize the differences among them at the neighborhood level in the extent of their segregation from other groups , and the degree to which they form separate residential enclaves in the metropolis….