More than 1 million immigrants enter the United States, legally and illegally, each year. Many experts credit the new arrivals with helping to create and sustain the nation's current economic prosperity. But others argue that while immigration gives employers access to a cheap and plentiful labor force, American workers suffer because the newcomers take jobs and suppress wage levels. Critics of the current policies call for stricter limits on immigration and a crackdown on U.S. employers who knowingly hire undocumented workers. But supporters of liberal immigration policies warn that severely limiting legal immigration will hurt the economy and that, in any event, employer sanctions are not effective.

David Masci specializes in social policy, religion and foreign affairs. Before joining CQ Researcher as a staff writer in 1996, he was a reporter at CQ's Daily Monitor and CQ Weekly. He holds a BA in medieval history from Syracuse University and a law degree from The George Washington University.