Immigrants supply skills that are in relatively short supply in the U.S. labor market and account for almost half of labor force growth since the mid-1990s. Migrant inflows have been concentrated at the low and high ends of the skill distribution. Large-scale unauthorized immigration has fueled growth of the low-skill labor force, which has had modest adverse fiscal and labor market effects on taxpayers and U.S.-born workers. This report shows that high-skilled immigration has been beneficial in most every way, fueling innovation and spurring entrepreneurship in the high tech sector. Highly skilled immigrants have had a positive fiscal impact, contributing more in tax payments than they use in public services. Immigration reform appears to be on the horizon, and policies such as a legalization initiative, a guest-worker program and more permanent visas for high-skilled workers would likely be an improvement over the status quo. Figures and tables. This is a print on demand report.