This book is the result of a joint research effort led by the U.S. National Academy of Sciences and involving the Royal Scientific Society of Jordan, the Israel Academy of Sciences and Humanities, and the Palestine Health Council. It discusses opportunities for enhancement of water supplies and avoidance of overexploitation of water resources in the Middle East. Based on the concept that ecosystem goods and services are essential to maintaining water quality and quantity, the book emphasizes conservation, improved use of current technologies, and water management approaches that are compatible with environmental quality.

In December 2002, a group of specialists on water resources from the United States and Iran met in Tunis, Tunisia, for an interacademy workshop on water resources management, conservation, and recycling. This was the fourth interacademy workshop on a variety of topics held in 2002, the first year of such workshops. Tunis was selected as the location for the workshop because the Tunisian experience in addressing water conservation issues was of interest to the participants from both the United States and Iran. This report includes the agenda for the workshop, all of the papers that were presented, and the list of site visits.

The report aims to provide a conceptual framework to address food security under conditions of water scarcity in agriculture. It has been prepared by a team of FAO staff and consultants in the framework of the project "Coping with water scarcity - the role of agriculture", and has been discussed at an Expert Consultation meeting organized in FAO, Rome, during the period 14-16 December 2009 on the same subject. It was subsequently edited and revised, taking account of discussions in the Expert Consultation and materials presented to the meeting. The purpose of the Expert Consultation was to assist FAO to better design its water scarcity programme. In particular, the experts were requested to provide recommendations on the range of technical and policy options and associated principles that FAO should promote as part of an agricultural response to water scarcity in member countries. The document offers views on the conceptual framework on which FAO's water scarcity programme should be based, proposes a set of definitions associated with the concept of water scarcity, and indicates the main principles on which FAO should base its action in support to its member countries. At the meeting, experts were requested to review the draft document and provide feedback and recommendations for its finalization. Issues that were addressed in discussions included: 3⁄4 Water scarcity: agreement on key definitions. 3⁄4 The conceptualisation of water scarcity in ways that are meaningful for policy development and decision-making. 3⁄4 The quantification of water scarcity. . 3⁄4 Policy and technical response options available to ensure food security in conditions of water scarcity. . 3⁄4 Criteria and principles that should be used to establish priorities for action in response to water scarcity in agriculture and ensure effective and efficient water scarcity coping strategies.

This Book includes selected papers that has been published in the Water journal Special Issue (SI) on Water Supply and Water Scarcity. Moreover, an overview of the SI is included. The papers selected for publication in the SI include review and research papers on water history, on water management issues under water scarcity regimes, on rainwater harvesting, on water quality and degradation, and on climatic variability impacts on water resources. Overall, the issue identify and highlight the main challenges in water sector, and particularly in management and protection of water resources and in use of alternative (non-conventional) water resources, especially in areas with demographic change and climate vulnerability in order to achieve sustainable and secure water supply. Furthermore, general guidelines and possible solutions for an improved and sophisticated water management system are proposed and discussed, such as the adoption of advanced technological solutions and practices that improve water-use efficiency and the use of alternative water resources, to address the growing environmental and health issues and to reduce the emerging conflicts among water users.