Nonimmigrant visas are for international travelers coming to the United States temporarily. The visa, placed in your passport when issued, allows you to travel to a port of entry and request the permission of the Department of Homeland Security Customs and Border Protection immigration officer to enter the United States. A visa does not guarantee entry. International travelers come to the United States for a wide variety of reasons, including tourism, business, medical treatment, and certain types of temporary work. For an overview of the types of nonimmigrant visas available, please see our Visa Categories page.