Theoretical interpretation of the role and potential of ASEAN (Association of Southeast Asian Nations) remains controversial. Three salient theoretical approaches, neo-realist, neo-liberal, and domestic factors, have provided crucial explanations of ASEAN's weaknesses. These attributes, however, lack essential analytical tools to interpret ASEAN's role and potential in creating regionalism and regionalization in East Asia in the post-Cold War era.Given both theoretical and operational levels, constructivism is a predominant approach to portray the role and potential of ASEAN, particularly the role it plays in creating an increasingly connected web of cooperation and in managing the regional frameworks and arrangements with its founding principles and norms. While the endeavour on regionalization driven by the ASEAN Way and principles is impressive, the 2008-adopted Charter has marked a crucial step in ASEAN's institutional and political development for regionalism. The marginalization of the ASEAN Way, however, remains a default norm. Thus, much needs to be done to bring about strong political will and commitment per se toward the realization of the ASEAN Community and toward East Asian regionalism.Keywords: theoretical approaches, the ASEAN (Association of Southeast Asian Nations) Way, regionalization, regionalism Explaining the role and potential of ASEAN (Association of Southeast Asian Nations) remains controversial theoretically. Neo-realists tend to focus on security and treat the balance of power as a key determinant of regional affairs and to be skeptical about the regional security management role played by ASEAN and about prospects for peaceful change. Neo-liberal theorists tend to prioritize their position on economic and institutional evolution and put their claims on ASEAN-driven regional projects characterized by low institutionalized frameworks and arrangements, thus leading to lacking high commitment required by institutions per se. While the two theoretical approaches are the major theoretical attributes to explain weaknesses of ASEAN in East Asian integration, domestic factors play a crucial role in capturing the understanding of interplay and interrelations between the impact of regionalism/regionalization and state behavior. Unlike the three above salient approaches, constructivist advocates focus their attention on ASEAN's ideational factors like norms, ideas, identity, and other cultural attributes through social-driven processes which contribute a great deal to creating an increasingly connected web of cooperation and which helps in turn enhance interaction of state actors for regional cooperation.