Water is becoming increasingly scarce. If recent usage trends continue, shortages are inevitable. Aquanomics discusses some of the instruments and policies that may be implemented to postpone, or even avoid, the onset of "water crises." These policies include establishing secure and transferable private water rights and extending these rights to uses that traditionally have not been allowed, including altering in-stream flows and ecosystem functions. The editors argue that such policies will help maximize water quantity and quality as water becomes scarcer and more valuable....