The National Counterintelligence and Security Center (NCSC) is the nation’s premier source for counterintelligence and security expertise and a trusted mission partner in protecting America against foreign and other adversarial threats. We lead and support the U.S. Government’s counterintelligence (CI) and security activities critical to protecting our nation; provide CI outreach to U.S. private sector entities at risk of foreign intelligence penetration; and issue public warnings regarding intelligence threats to the U.S.