[Excerpt] The United States has long distinguished temporary migration from settlement migration. The Immigration and Nationality Act (INA) establishes the circumstances under which foreign nationals may be admitted temporarily or come to live permanently Those admitted on a permanent basis are known as immigrants, or lawful permanent residents (LPRs), while those admitted on a temporary basis are known as nonimmigrants. The INA provides for the admission of nonimmigrants for designated periods of time and a variety of specific purposes. Nonimmigrants include tourists, foreign students, diplomats, temporary agricultural workers, cultural exchange visitors, internationally known entertainers, foreign media representatives, intracompany business personnel, and crew members on foreign vessels, among others.
Policy discussions about nonimmigrant admissions are as varied as the visa classes under which temporary migrants enter. Tourists, business visitors, and foreign students, for example, are usually seen as a boon to the U.S. economy, while the economic costs and benefits of temporary workers are hotly debated. In addition, cultural exchange programs are a foreign policy tool, intended to foster democratic principles and spread American values across the globe, but some of these programs that include work authorization have come under scrutiny for an alleged lack of protections for both U.S. workers and program participants. Further, the entry of nonimmigrants has prompted national security concerns—particularly over those who enter under the Visa Waiver Program. Debates also continue over the implementation of a system to document the exits of foreign nationals from the United States, as nonimmigrants who remain in the country after their visas expire are accounting for a growing share of the unauthorized alien population.
Achieving an optimal balance among policy priorities—ensuring national security, facilitating trade and commerce, supporting fair labor practices, protecting public health and safety, and fostering international cooperation—remains a challenge. As policymakers consider modifying nonimmigrant visa categories, they may be interested in learning more about each of the categories and their relationship to the policy priorities. This report explains the statutory and regulatory provisions that govern nonimmigrant admissions to the United States before turning to a description of the major nonimmigrant categories. It describes trends in temporary migration, including changes over time in the number of nonimmigrant visas issued and nonimmigrant admissions. Estimates of nonimmigrants who establish residence in the United States are briefly discussed, as are estimates of those who stay beyond their authorized period of admission. The report concludes with a detailed table showing key admissions requirements across all nonimmigrant visa types.