U.S. Citizenship and Immigration Services (USCIS) is the government agency that oversees lawful immigration to the United States. Field offices in the U.S. and its territories provide: *Interviews for all non-asylum cases (for example, getting a Green Card); *Naturalization ceremonies; and *Appointments for information and applicant services that supplement what we provide through our website and by phone (for example, case-specific scenarios that require in-person help).