For the increasing role of Thailand on issues related to natural resources and environment sustainable in the global and the ASEAN community, it is necessary to utilize the results of conferences and declarations in both global and ASEAN level for developing guidelines and proper operation with Thai society. The Office of Natural Resources and Environmental Policy and Planning, as a unit of national coordinating environmental sustainable cities in the ASEAN, give precedence on formulating strategics on driving ASEAN cooperation and initiative on environmentally sustainable cities such as promotion of the use of sufficiency economy principle to conduct Thai community to low carbon society and the environmentally friendly cities, city development toward clean and green city, finding necessary tools and proper support to local government organizations and various sectors of the community to have a concrete result achievement on the city management to low carbon society, and sharing urban/city development experience of with ASEAN countries, to strengthen the role of Thailand as above. For this reason, it become the origin of this project.