Nonimmigrant visas are issued to foreign nationals seeking to enter the United States on a temporary basis for tourism, business, medical treatment, and certain types of temporary work. The type of nonimmigrant visa needed is defined by immigration law and related to the purpose of the travel.

Generally, an individual applies directly to the U.S. consulate or embassy abroad for a tourist (B-2) or business nonimmigrant (B-1) visa. But foreign nationals seeking to enter the United States to study or work may require certain authorization and documentation prior to applying for a nonimmigrant visa. For an alphabetical listing all of the nonimmigrant visa classifications and specific requirements, refer to the United States Citizenship and Immigration Services (USCIS) website, or the U.S. Department of State website.

Issuance of a visa does not guarantee entry to the United States. A visa simply indicates that a U.S. consular officer at an American embassy or consulate has reviewed the application and that officer has determined that the individual is eligible to enter the country for a specific purpose. The U.S. Customs and Border Protection (CBP) Officer at the port-of-entry will conduct an inspection to determine if the individual is eligible for admission under U.S. immigration law.

In Delaware, as in all U.S. states, the regulation of nonimmigrant visas is a federal matter, governed by immigration law and administered by federal agencies such as the United States Citizenship and Immigration Services (USCIS) and the U.S. Department of State. Nonimmigrant visas are for foreign nationals who intend to stay in the United States temporarily. The type of visa required depends on the purpose of their travel, whether it's for tourism (B-2), business (B-1), medical treatment, study, temporary work, or other approved activities. Applicants must apply for these visas at a U.S. consulate or embassy in their home country, providing the necessary documentation and demonstrating their intent to return to their home country after their temporary stay. The issuance of a visa does not guarantee entry into the U.S.; this is determined by CBP officers at the port-of-entry based on eligibility for admission under U.S. immigration law.