Professor Chawalit Rattanatammasakul, Ph.D. is a professor and committee of the Faculty of Engineering (Environmental Engineering) from Chulalongkorn University. The professor was offered the scholarship from the Japanese government (Monbusho scholarship) to study the Master and Doctorate degree in the field of Environmental Engineering with the current interesting research topics; Global Warming Mitigation, Circular Economy Development, Sustainable Environmental Management, Water Reuse & Recycling, Zero Waste Strategy, Renewable Energy Development. The professor has experience as being an honorary specialist at the international level, for instance, Chairman of Thailand Chapter, International Water Association (IWA) and International Associate Member of Japan Society on Water Environment (JSWE). At the national level, the professor has also been the board member of the Engineering Institute of Thailand Under H.M. the King’s Patronage, Chairman of the subcommittee directing the standard of sewerage control from the source of water pollution for the Ministry of Natural Resources and Environment, committee directing wastewater treatment construction design project of Bangkok Metropolitan. The professor has also attended many projects.