The article is focused on military integration and its influence on the post-soviet space. The main object of the research is the Collective Security Treaty Organization, which connects a part of the territory of the former Soviet Union. The organization in itself, its functions and military activities have not been discussed and analyzed. This is one of a few organizations that forms military forces and tries to respond to security challenges at a regional level. The article is divided in two main parts. The first part explains the phenomenon of military integration and its influence on the political military cooperation between national states. Military integration is a new element in political science therefore the research attempts to give details on the subject and to divide it into stages. This might serve well for future research or studies on military alliances. The second part places an heavy emphasis on the Collective Security Treaty Organization, its formation, legal basis and military structure. By using the model of military integration stages, the article comes to the conclusion that the organization has entered the last stage of military integration, which it identifies as functional dependency. Military forces have become inter-operable and a joint command system ensures further credible integration.