Spec - STAR
- Special Consultative Group
- Special International Council
- Special Operations Command
- Special Operations Forces
- special purpose troops
- Special Representative
- Special Representative of the UN Secretary General
- special services
- spetsnaz
- spheres of influence
- Spillover Monitor Mission to Skopje
- splinter organization
- SPOD
- Spokesman's Service
- SRSG
- Stability and Support Operations
- Stability Pact
- Stability Pact for South Eastern Europe
- stabilization force
- staff officer
- staff post
- Staff Regulations
- STANAVFORCHAN
- STANAVFORLANT
- STANAVFORMED
- Standard Operating Procedure
- Standing Committee on Military Matters
- Standing Naval Force Atlantic
- Standing Naval Force Channel
- Standing Naval Force Mediterranean
