'Water Crises', 'Water Wars', 'Peak Water' and many more phrases have been used in recent years to suggest that a growing population and increased per capita water use are leading inexorably to critical levels of water scarcity. In this talk, the factors affecting water availability and water use are explained and the links between water use, population growth, economic output, social welfare and ecosystem services are examined. Against this background, alternative 'water futures' are presented to illustrate the potential for sustainable water use, and the challenges of imagination, economics and governance that may be required to steer a path to sustainability.