This book summarises the recent, and future, sustainable, low-cost, environment-friendly and efficient systems for clean water production, to solve clean water crisis. We cover production of water the dew and rain or via desalination, Fenton processes or electrocoagulation; nanomaterial-based water purification methods including adsorption, catalysis, smart-sensors for pollutants detection and removal. We also cover environmental management, environmental policy aspects, and review recent patents and industrial processes to produce clean water. Written by experts in the domain of wastewater treatment, production of clean water and environmental management, this new book will be a unique tool for experts and students. We anticipate it open new horizons in clean water production and will be a source of inspiration for next generations of clean water technologies researchers