The U.S. Citizenship and Immigration Services (USCIS) is a federal agency through which the Department of Homeland Security (DHS) provides various immigration services. The USCIS offers immigration-related services through its official website as well through offices located across the country and overseas.
In the U.S., the USCIS has divided the country into 4 regions (Northeast, Southeast, Central, and Western) with each region having a regional director. The regions are further divided into 26 districts. Within each district, there may be several field offices.