The shortage of fresh water is likely to be one of the most pressing issues of the twenty-first century. A UNESCO report predicts that as many as 7 billion people will face shortages of drinking water by 2050. Here, David Lewis Feldman examines river-basin management cases around the world to show how fresh water can be managed to sustain economic development while protecting the environment. He argues that policy makers can employ adaptive management to avoid making decisions that could harm the environment, to recognize and correct mistakes, and to monitor environmental and socioeconomic changes caused by previous policies. To demonstrate how adaptive management can work, Feldman applies it to the Delaware, Susquehanna, Apalachicola-Chattahoochee-Flint, Sacramento-San Joaquin, and Columbia river basins. He assesses the impacts of runoff pollution and climate change, the environmental-justice aspects of water management, and the prospects for sustainable fresh water management. Case studies of the Murray-Darling basin in Australia, the Rhine and Danube in Europe, the Zambezi in Africa, and the Rio de la Plata in South America reveal the impediments to, and opportunities for, adaptive management on a global scale. Feldman’s comprehensive investigation and practical analysis bring new insight into the global and political challenges of preserving and managing one of the planet’s most important resources.