Administers immigration and naturalization functions and establishes immigration services policies and priorities. It handles immigrant visa petitions, naturalization petitions, asylum and refugee applications and changes in green card status. In addition to the laws, forms, services, and educational information on immigration, the USCIS website also has information on filing immigration-related Freedom of Information/Privacy Act (FOIA) requests and a genealogy section with information about immigration history and how to find out more information about immigrant relatives.

Under the Violence Against Women Act (VAWA), battered immigrants can petition for legal status in the United States without relying on abusive US citizen or legal permanent resident spouses, parents or children to sponsor them.