The use of urban wastewater in agriculture is receiving renewed attention, with the increasing scarcity of fresh water resources in many arid and semi-arid regions of the world. Wastewater is a low-cost alternative to conventional irrigation water, although it may carry health and environmental risks.This book critically reviews experience worldwide of these issues. Emphasis is placed on untreated wastewater use by means of field-based case studies from Asia, Africa, the Middle East and Latin America. It brings together a range of perspectives including economic, health, agronomic, environmental, institutional, and policy dimensions.