This text is divided into three parts. Part I focuses on the need for management to assess the challenges of water scarcity and plan changes based on proper valuation and financial instruments, international co-operation and efficient use. Part II analyses the problems of water scarcity and the available solutions in each main sector: water supply and sanitation, energy, health, agriculture, ecosystems and biodiversity. Part III assesses the state of the debate following the third World Water Forum and sets out the priorities for action, including increased investment, institutional reform and capacity building in the water sector. Downloadable resources with extensive case studies and statistical data accompanies this text.