WEPA and the Ministry of Environment of Indonesia have jointly organized the WEPA Workshop on “Decentralized Domestic Wastewater Treatment in Asia” on 14th November in Jakarta, Indonesia. About 30 policy makers and water professionals of related governmental ministries and NGOs from Indonesia, Japan, Thailand and Vietnam have participated and contributed to the workshop. The purpose of this workshop is to share the technologies and management situation of decentralized domestic wastewater applied in WEPA member countries through a number of presentations at the workshop and actual site visits. In the workshop, participants discussed about the feasibility of decentralized domestic wastewater management systems in Asian countries. After the workshop, all participants had chance to pay a visit to a model SANIMAS project site of Indonesia government in Bekasi City. In addition, workshop participants attended the workshop on model project of Johkasou (Japanese decentralized domestic wastewater treatment system) organized by Kubota Corporation on 13th November in Jakarta.