* Founded on October 7, 2002 by Armenia, Belarus, Kazakhstan, Kyrgyzstan, Russia, and Tajikistan

* Evolved from the CIS Collective Security Treaty, which was signed in 1992 and came into force in 1994. Moldova and Ukraine were observers. Azerbaijan, Georgia, and Uzbekistan withdrew in 1999

* Registered with the UN in 2003

* Main objectives: ensuring peace, preserving the territorial integrity of member countries, coordinating activities in the fight against international terrorism, drug trafficking, and organized international crime, and providing immediate military assistance to a CSTO member in the event of a military threat.

* Some experts say the CSTO was created to prevent NATO's further eastward expansion and keep some CIS countries under Russia's military protection

* Has a Collective Rapid Reaction Force with 1,500 military personnel deployed in Kazakhstan, Kyrgyzstan, and Tajikistan. Continues to create military groups and supply them with munitions

* Nikolai Bordyuzha is CSTO secretary-general