Today's irrigation management faces challenges and competition with other sectors (ie: household, industry, and environmental), quality degradation, and uncertain climatic conditions. To cope with these situations, the irrigation managers need precise estimation/determination of irrigation needs for crops, advance/water-saving techniques for water application, water conservation approaches, economic considerations in irrigation, and potentials for using marginal quality water in irrigation (such as saline water, and waste-water). This book focuses on all of the above issues: starting with irrigation management strategies for field crops -- to suitability of saline and waste-water as irrigation water. The book is useful to identify the need and adopt emerging technologies for irrigation management, as well as to identify appropriate methodologies for social, economic, and environmental benefits of improved irrigation management.