CSTO
Collective Security Treaty Organization
Updated 7 November 2026
The Russia-led collective-defence treaty for parts of the post-Soviet space. Its only collective deployment was to Kazakhstan in January 2022; Armenia froze participation in 2024.
Key facts
- Founded
- 2002
- Headquarters
- Moscow, Russia
- Members
- 5 states
- Chair
- Russia
- Secretary-General
- Taalatbek Masadykovsince January 2026
- Next summit
- 11 November 2026Moscow, Russia
- Last summit
- 27 November 2025Bishkek, Kyrgyzstan
- The UAE
- Not a member
- UAE trade with members (2025)
- $9.9 billion