Because water access, distribution and quality are the most urgent challenges for societies across the world, this book focuses on the current and future demands and challenges in the areas of water scarcity we may face and possible solutions in terms of technology and management including infrastructure changes that are needed for the future smart cities. Readers of this book shall gain an increased understanding of water supply and its demands and shall learn some of the research trends to overcome global water scarcity and urban growth by creating smart cities.