In addition to existing gas producing countries, there are several emerging countries in Southeast Asia that are promoting gas production and use. Since rising energy needs will increase Asia’s dependency on imported oil, the further development of gas resources will play an increasingly important role in improving energy security and in providing environmental protection for the region. This study, a follow-up to the IEA’s Asia Gas Study (1996), describes the current situation, uncertainties and future challenges in the gas sectors of the Philippines, Vietnam and Myanmar. Over the next ten years, the role of natural gas will expand steadily in these countries. The development of gas sectors could also encourage the construction of a gas pipeline network in Southeast Asia.