# DCSA The **Defense Counterintelligence and Security Agency**, a Department of Defense component and the federal government's primary background-investigation provider — it conducts roughly 95% of federal personnel-security investigations, for DoD and for the civilian agencies that have transferred the function to it. ## Why it sits where it does DCSA absorbed the investigative workload that had migrated from OPM to the short-lived National Background Investigations Bureau after the 2015 OPM breach, and merged it with the former Defense Security Service. The result is unusual: a single Defense component investigates the cleared population of the entire executive branch, while the policy authority over what those investigations mean sits elsewhere — with the DNI as Security Executive Agent and the OPM Director as Suitability and Credentialing Executive Agent. ## Functions - Background investigations for national-security eligibility (Tier 3 and Tier 5) and for suitability - Continuous vetting operations under SEAD 6 and Trusted Workforce 2.0 - Administration of the National Industrial Security Program for cleared contractors - Counterintelligence and insider-threat support - Development and operation of **NBIS**, the National Background Investigation Services system intended to replace the legacy investigative stack — years behind schedule, with full deployment projected for FY2027 ## Leadership Joseph Tonon was reported in May 2026 as incoming director, succeeding Justin Overbaugh, who served as acting director while also holding the Deputy Under Secretary of Defense for Intelligence and Security post. `[unconfirmed]` — from trade reporting, pending a primary agency source. ## See also - [[How a Security Clearance Is Granted and Revoked]] - [[Federal Workforce Structure Tree]] - [[Intelligence Community Tree]] - [[Federal Agencies Hub]] ---