The latest edition of Congressional Research Service Report R43753, prepared in August 2016. Temporary visas for professional, managerial, and skilled foreign workers have become an important gateway for high-skilled immigration to the United States. Over the past two decades, the number of visas issued for temporary employment-based admission has more than doubled from just over 400,000 in FY1994 to over 1 million in FY2015. While these visa numbers include some unskilled and low-skilled workers as well as accompanying family members, the visas for managerial, skilled, and professional workers dominate the trends. Since 1952, the Immigration and Nationality Act (INA) has authorized visas for foreign nationals who would perform needed services because of their high educational attainment, technical training, specialized experience, or exceptional ability. Today, there are several temporary visa categories that enable employment-based temporary admissions for highly skilled foreign workers. These visa categories are commonly referred to by the letter and numeral that denote their subsection in the INA. They perform work that ranges from skilled labor to management and professional positions to jobs requiring extraordinary ability in the sciences, arts, education, business, or athletics. Policymakers and advocates have focused on two visa categories in particular: H-1B visas for professional specialty workers, and L visas for intra-company transferees. These two nonimmigrant visas epitomize the tensions between the global competition for talent and potential adverse effects on the U.S. workforce. The employers of H-1B workers are the only ones required to meet labor market tests in order to hire professional, managerial, and skilled foreign workers. Although foreign students on F visas are generally barred from off-campus employment, some F-1 foreign students are permitted to participate in employment known as Optional Practical Training (OPT) after completing their undergraduate or graduate studies. OPT is temporary employment that is directly related to an F-1 student's major area of study. Generally, an F-1 foreign student may work up to 12 months in OPT status. In 2008, the Bush Administration added a 17-month extension to OPT for F-1 students in STEM fields, and the Obama Administration recently proposed a 24-month extension for F-1 students in STEM fields. Congress has an ongoing interest in regulating the immigration of professional, managerial, and skilled foreign workers to the United States. This workforce is seen by many as a catalyst of U.S. global economic competitiveness and is likewise considered a key element of the legislative options aimed at stimulating economic growth. The challenge central to the policy debate is facilitating the migration of professional, managerial, and skilled foreign workers without putting downward pressures on U.S. workers and U.S. students entering the labor market.