A series of dams on the transboundary Mekong River has reduced water levels, damaging fisheries and causing other environmental problems for the people who depend on the waterway for their livelihoods and food. Now, as the latest dam, the Lao-owned Xayaburi, begins operations on the Lower Mekong, a Thai activist group is going to court to slow down the sale of electricity to Thai companies. Steve Sandford speaks to those affected.