Following the historical review of the establishment of the regional security governance in post-Soviet Eurasia and review of the political and military components of the regional military alliance, the aim of this chapter is to explore the distribution of military power among the CSTO allies and to examine the military potential of each member in terms of its ability to provide a necessary military assistance in case of aggression against any ally, i.e., Article 4-interventions. Accordingly, this chapter focuses on examination of the military characteristics of the allies. Specifically, we review the objective military capabilities of the CSTO member-states. Such review will allow us to clarify the following questions: What is the military power of each of the allies? What is the potential contribution of each member of CSTO to the collective defense of the alliance? What is the specific mix of military capabilities of the five smaller members (Armenia, Belarus, Kazakhstan, Tajikistan and Kyrgyzstan) and the dominant military power, Russia, within the alliance? For the purposes of the examination, we turn to the two following indicators-size of the national armed forces of the CSTO states and their respective military expenditures. We begin the discussion by referring to the rationale behind the selection of these indicators for examining the military power of the states and operationalization thereof. We proceed with the review of the military power of each of the six allies. Accordingly, the chapter will be divided into six sub-chapters, each devoted to