By 1988, the Mexican-origin population of the United States had grown to 12.1 million, largely from recent sharp increases in immigration. The policy concerns raised by this phenomenon have been influenced by some perceptions that available research contradicts. Today most Mexican immigrants come to stay, about half are female, and they have increasingly less schooling compared with the native-born workers, and, across generations, their language and political assimilation is proceeding well. They put greater demands on education than on other public services. However, the Mexican-origin population affects the economy and public services more and differently in the areas where it is concentrated, primarily in the western United States and large urban areas. Further, the recent legalization of 2.3 million Mexican immigrants can be expected to increase the demand on public services, especially in those areas.