This report describes the foreign-born population in the United States in 2003. It provides a profile of demographic and socio economic characteristics, such as region of birth, geographic distribution in the United States, age, educational attainment, earnings, and poverty status. These characteristics are compared with those of the native population and, because the foreign born are a heterogeneous group, variability within the foreign-born population is also discussed. The findings are based on data collected by the Census Bureau in the Current Population Survey (CPS). The foreign born are those who were not U.S. citizens at birth. Natives are those who were born in one of the following areas the United States, Puerto Rico, Guam, American Samoa, the U.S. Virgin Islands, or the Northern Mariana Islands or were born abroad of at least one parent who was a U.S. citizen. [This report was partially funded by the Office of Immigration Statistics, Department of Homeland Security.]