Water is a basic human need and a scarce commodity with increasing value to farmers, industries, and cities in an urbanizing world. It is unpredictable in supply and quality, difficult to contain or direct, and notoriously difficult to manage well. Several trends -- climate change, the endurance of widespread global water poverty, intensifying competition among rival uses and users, and the vulnerability of critical freshwater ecosystems -- combine to intensify the challenges of governing water wisely, fairly, and efficiently. The twenty-seven chapters in The Oxford Handbook of Water Politics and Policy address such issues over the course of seven thematic sections. These themes reflect familiar frameworks in the water policy world, including water, poverty, and health; water and nature; and water equity and justice. Other sections look at emergent and contentious policy arenas, including the water/energy/food nexus and management of uncertainty in water supply, or connect well-established strands in new ways, including sections on water tools (water price and value, supply and demand, privatization, corporate responsibility) and issues surrounding transboundary waters. This volume conceives of water as a global issue, and gathers a diverse group of leading scholars of water politics and policy.