This book addresses several aspects of water scarcity and its management to save the world and for a sustainable life. It discusses about irrigation water quality and criteria to determine water quality. It covers management issues and soil responses to the use of irrigation water of varying quality.This book emphasizes about the wastewater which must be treated to ensure a safe environment and foster public health. Effluent which meets set discharge standards can be appropriately used for aquaculture and also irrigation. This book highlights different types of droughts and their management. In addition, this book also combines the latest information on water stress and frequently encountered abiotic stress in the terrestrial surface. Its deleterious effects on plant growth and productivity. This book further discusses the strategies to improve the agriculture, especially in the climate change situation.The book is a resourceful read for students, teachers, and readers including engineers and researchers in water technology.