Living River Siam is a Thai non-governmental organization (NGO) which analyzes the impact of Thailand's various dam projects and coordinates the research of indigenous peoples to give Thai villagers the power to document the influence of local rivers and dams. Founded in 1999, it gained prominence during the Pak Mun Dam study period in 2001, when it developed a method for instructing villagers on how to document the effects of the dammed river on their lives. When the Thai government proposed other dam sites, Living River Siam took its research methods to the villages surrounding those sites as well. Today, the organization works with other NGOs in Southeast Asia to counter government-sponsored research that encourages dam construction.

The Pak Mun Dam is a barrage dam and run-of-the-river hydroelectric plant 5.5 km west of the confluence of the Mun and Mekong Rivers in Khong Chiam District, Ubon Ratchathani Province, Thailand. It was constructed by the Electricity Generating Authority of Thailand (EGAT) with support from the World Bank at a total cost of US$240 million, and completed in 1994.