Security Service
- List of security agencies
- MI5
- National Intelligence and Security Service (disambiguation)
- National Security Service (disambiguation)
- Private military company
- Private security company
- RCMP Security Service
- Secret police
- Secret service
- Security Intelligence Service (disambiguation)
- Security agency
- Security and Intelligence Services (India)
- Security service (telecommunication)
- Sicherheitsdienst
- Swedish Security Service
- United States Air Force Security Service