This chapter analyses the evolution of the security endeavors and describes the key trends in the SCO's security development. The authors outline the regional security approaches practiced by the SCO states: Russia's “post-Soviet regionalism,” China's “Asian regionalism,” and the CA members' “virtual regionalism.” Next, we define the two main stages of the development of the SCO's regional security system: the period 200-2015 during which the Organization's CA security system was established; and the period 2015-2017, when India and Pakistan joined the Organization, marking a new stage of building a regional security system, extending beyond the borders of the former Soviet republics, which is referred to as “Greater Eurasia.” The authors analyze the process of shaping the SCO's security agenda, from conventional security matters to non-military issues. They draw the conclusion that the modern SCO is increasingly adopting the “Asian” model of regional security, the distinctive feature of which is an emphasis on confidence-building measures and non-legally binding arrangements in the “Greater Asian” space.