Book excerpt: Properly treated sewage effluent becomes an alternative source of irrigation water, and at the same time it provides a convenient means of sewage disposal through land treatment to prevent potential health and environmental hazards caused by uncontrolled flow of wastewater. The objective of this volume is to provide the reader with a comprehensive up-to-date overview of the principles and practices of irrigation with treated sewage effluent, including special reference to arid quality of the water (e.g. pathogenic organisms, salt, nutrients). The present volume describes the main components of effluent-soil-plant systems involved in the development of appropriate irrigation-fertilization-cropping management for optimizing crop production. Comprehensive information has been suggested on the following subjects: 1. source, treatment and properties of sewage effluent; 2. main processes of different effluent constituents on soil-plant systems; 3. irrigation-fertilization management; 4. irrigation systems for sewage effluent.