Immigration gives the United States an economic edge in theworld economy. Immigrants bring innovative ideas andentrepreneurial spirit to the U.S. economy. They provide businesscontacts to other markets, enhancing America's ability to trade andinvest profitably in the global economy. They keep our economyflexible, allowing U.S. producers to keep prices down and torespond to changing consumer demands. An authoritative 1997 studyby the National Academy of Sciences (NAS) concluded thatimmigration delivered a "significant positive gain" to the U.S.economy. In testimony before Congress last year, Federal ReserveBoard Chairman Alan Greenspan said, "I've always argued that thiscountry has benefited immensely from the fact that we draw peoplefrom all over the world."