The H-1B is a classification of non-immigrant visa in United States that allows U.S. employers to hire foreign workers in specialty occupations, as well as fashion models, or persons who are engaged in Department of Defense projects who meet certain conditions. The regulation and implementation of visa programs are carried out by the United States Citizenship and Immigration Services (USCIS), an agency within the United States Department of Homeland Security (DHS). Foreign nationals may have H-1B status while present in the United States, and may or may not have a physical H-1B visa stamp.