Two hydropower giants account for over half of the world’s dams, yet the biodiversity impacts of their projects remained largely unanalyzed and overlooked in planning processes. A new report, Advancing Ecological Civilization?, examines the biodiversity footprint of the world’s two largest dam-builders, PowerChina and China Three Gorges. It calls attention to the need for dam building companies to take urgent steps to address the increasing scale and severity of their environmental impacts.