Analyzing the Achievements of the Greater Mekong Subregion (GMS): The Impact of Subregional Cooperation on Security & Peace KRAHLTIMOTHEUS JOHANNES 2018 The PhD thesis explores and advances the Security Community framework by Karl W. Deutsch. In doing so it reviews the social constructivist contributions to the discourse and synthesizes the approaches, bringing forward the Three Pillared Security Community framework. Based on the advanced approach to study Security Communities the Greater Mekong Subregion (GMS), an economic development cooperation in mainland Southeast Asia, is analyzed. Thereby the thesis makes the argument that intra-regional development contributes to peace and security and evaluates if this is the case.