Immigration, both legal and illegal, has a profound impact on the United States. The public policy implications of immigration include the impact on population growth, employment, wages, taxes, and social spending. In 1994, a net total of between 900,000 and 1.1 million immigrants were added to the foreign-born population of the United States. Over 800,000 of these immigrants were legally admitted to the United States, and it is estimated that undocumented immigration accounted for another 200,000 to 300,000 additions. Over 40% of the legal immigrants arrived from the "Americas," and just under two-thirds of the estimated illegal immigrant population came from Central America and the Caribbean. The characteristics and experiences of immigrants vary widely across education, economic, and social spectrums, with immigrants overrepresented among the least well educated and the most well educated portions of the U.S. population. Immigrants and their offspring are expected to contribute two-thirds of the population growth in the United States between 1990 and 2040. Studies that have measured the impact of immigration on wage levels and job availability have indicated that immigration has a negligible impact on the overall U.S. labor market. In areas where low-wage, low-skill jobs comprise a significant portion of the economy and immigration is high, immigration does contribute to reduced earnings for low-skill workers. Recent surveys have also indicated that, in terms of taxes and social spending, immigrant households are an asset to the federal government, but that social spending and tax revenue attributable to immigrants generally offset each other on the state level. (Contains five graphs.) (SLD)