The immigration law provides several categories of nonimmigrant work visas for persons who wish to work temporarily in the United States. There are annual numerical limits on some classifications.

H-1B work visa applies to persons in a specialty occupation which requires the theoretical and practical application of highly specialized knowledge requiring completion of a specific course of higher education. This visa requires a labor attestation issued by the Secretary of Labor. This type of visa also applies to Government-to-Government research and development, or coproduction projects administered by the Department of Defense.

H-2A work visa applies to temporary or seasonal agricultural workers.

H-2B work visa applies to temporary or seasonal nonagricultural workers. This classification requires a temporary labor certification issued by the Secretary of Labor.

H-3 work visa applies to trainees other than medical or academic. This classification also applies to practical training in the education of handicapped children.

L visa types apply to intracompany transferees who, within the three preceding years, have been working abroad continuously for one year, and who will be employed by a branch, parent, affiliate, or subsidiary of that same employer in the U.S. in a managerial, executive, or specialized knowledge capacity.

O-1 visa applies to persons who have extraordinary ability in the sciences, arts, education, business, or athletics, or extraordinary achievements in the motion picture and television field.

O-2 visa applies to persons accompanying an O-1 alien to assist in an artistic or athletic performance for a specific event or performance.

P-1 visa applies to individual or team athletes, or members of an entertainment group that are internationally recognized.

P-2 visa applies to artists or entertainers who will perform under a reciprocal exchange program.

P-3 visa applies to artists or entertainers who perform under a program that is culturally unique (same as P-1).

Q-1 visa applies to participants in an international cultural exchange program for the purpose of providing practical training, employment, and the sharing of the history, culture, and traditions of the alien's home country.