In line with the Water Framework Directive, this book stresses the need for an Integrated Water Resources Management (IWRM) approach to balance the competing demands on water-domestic, agricultural, industrial, tourism and environmental/ecological- and promote economically efficient, socially equitable and environmentally sustainable water use in selected regions from Southern Europe, the Mediterranean and the developing world. Results from the research projects covered by this book, demonstrate that effective water management tools and decisions-making practices, are needed in order to complement integrated interventions for increasing the availability of supply and/or managing the growing demand for scarce water supplies. Further, the book attempts to bridge the gap between ideas and actions endorsed at the research-oriented environmental debate, and their translation into policy making structures and programs in developed and developing countries.