The book talks about functions of natural wetland namely That Luang Marsh in Vientiane Capital that play an important role of wastewater treatment for city. Currently, Vientiane's economy is rapidly expanding and increasing the density of people and built environment as well as concomitant land use changes. the book focuses on development around this marsh and domestic wastewater management of people living around the marsh and the way to improve people's behavior on wastewater management.