Green supply chain management is a concept that is gaining popularity in the South East Asian region. For many organizations in this region it is a way to demonstrate their sincere commitment to sustainability. However, if green supply chain management practices are to be fully adopted by all organizations in South East Asia, a demonstrable link between such measures and improving economic performance and competitiveness is necessary. This paper endeavors to identify potential linkages between green supply chain management, as an initiative for environmental enhancement, economic performance and competitiveness amongst a sample of companies in South East Asia. For this purpose a conceptual model was developed from literature sources and data collected using a structured questionnaire mailed to a sample of leading edge ISO14001 certified companies in South East Asia followed by structural equation modelling. The analysis identified that greening the different phases of the supply chain leads to an integrated green supply chain, which ultimately leads to competitiveness and economic performance. Future research should empirically test the relationships suggested in this paper in different countries, to enable comparative studies. A larger sample would also allow detailed cross-sectoral comparisons which are not possible in the context of this study. This paper presents the first empirical evaluation of the link between green supply chain management practices and increased competitiveness and improved economic performance amongst a sample of organizations in South East Asia.