This book describes the water security challenges with focus on water scarcity and quality in our rapidly changing world. Achieving water security is essential to promoting economic and social development, as well as resource sustainability and ecosystem integrity. Questions of water security are central to recent global agreements such as the Sustainable Development Goals (SDGs), the Paris Agreement on Climate Change, and the Sendai Framework for Disaster Risk Reduction. The thematic areas discussed here support the SDGs, with special attention to Goal 6 ("e;Ensure availability and sustainable management of water and sanitation"e;). The book  is a collection of studies from engineering, social and environmental disciplines and aims at giving a balanced overview of  the current , complex discourse on water scarcity and quality.It offers a source of inspiration and information for researchers, policymakers, planners, and practitioners concerning the further development of concepts, approaches, and methodologies for promoting water secure societies.

Introduction.- Water Security Assessment for the Red – Thai Binh River Basin, Vietnam.- Contextualizing Farmers’ Perceptions of Agricultural Wastewater Reuse in Areas of Water Shortage and Contamination: An In-depth Case Study of Wadi Al-Far`a Watershed – Palestine.- Optimize Anaerobic Degradation Processes in Agricultural Wastewater Treatment to maximize Biogas Productivity.- Evaluation of Wastewater Treatment using Dilution in Rosetta Branch and Tala Drain, Nile Delta, Egypt.- Upcoming Challenges of Water Reclamation fromUnconventional Sources.- How Membrane Bioreactor Technology Can Help to Solve both, German and RussianWastewater Problems.- Experiences on Wastewater Treatment and Reuse for Different Types of Industries.- Social Characteristics and Adaptation to Water Scarcity: The Case of Groundnut Farmers in the Lawra and Nandom Districts, Ghana.- Temporal Climate Variability and Staple Cereals in Southern Burkina Faso.