The Immigration and Nationality Act (INA) specifies a complex set of numerical limits and preference categories that include economic priorities among the criteria for admission. The INA allocates 140,000 visas annually for employment-based legal permanent residents (LPRs), and they were 14.2% of the total 1.0 million LPRs in 2010. The INA further specifies that each year, countries are held to a numerical limit of 7% of the world-wide level of U.S. immigrant admissions, known as per-country limits or country caps. Even as U.S. unemployment levels remain high, some employers assert that they continue to need the best and the brightest workers, regardless of the country of birth, to remain competitive in a world-wide market and to keep their firms in the United States. While support for the option of increasing employment-based immigration may be dampened by economic conditions, proponents argue it is an essential ingredient for economic growth. This book provides an overview of employment-based immigration and its economic considerations.