America today is witnessing the largest and most sustained wave of immigrants its borders have ever seen. Although factors like the Great Depression, World War II, and quota restrictions had slowed the massive influx of Europeans from the early part of the 20th century, policies like the 1965 Immigration and Nationality Act have relaxed quotas and opened America's doors to hundreds of thousands of immigrants a year, from both Eastern and Western hemispheres, to reach a height of over 9 million immigrants in the 1990s. Today, immigrants and policy-makers alike grapple with issues regarding employment, education, refugee status, and family reunification; as well as illegal immigrants - many from Mexico, whose legal immigration alone accounts for more than 20 per cent of immigrants in the US. Despite this, this comprehensive reference source allows a glimpse of the same motivating factors that drove earlier immigrants through Ellis Island's gates - the promise of economic opportunity and the hope of a better life. Over 70 A-Z entries address topical and timely aspects of modern US immigration, including: bilingual education; domestic work; employer sanctions; gangs; gender; homeland security; migrant education; posttraumatic stress disorder; and stereotypes.