This collection of papers examines water management in two of the world's prominent, arid transboundary areas facing similar challenges. In the Middle East, the chronically water-short Israeli-Palestinian region has recognized the need both to conserve and supplement its traditional water sources. Across the globe on the North American continent, Arizona--a state in the southwestern United States bordering Mexico--relies significantly on the overallocated Colorado River, as well as on non-renewable groundwater supplies. For both regions, sustainable and cost-effective solutions clearly...