1.1 General Framework In most arid and semi-arid countries, water resource management is an issue that is both important and controversial. Most water resources experts now acknowledge that water conflicts are not caused by physical scarcity but are mainly due to poor water management (Rosegrant et al. 2002; Benoit and Comeau 2005; Comprehensive Assessment of Water Management in Agriculture 2007; Garrido and Dinar 2010, among others). The scientific and technological advances of the past 50 years have led to new ways to solve many water-related conflicts, often with tools that seemed unthinkable a few decades ago (Llamas 2005; Lopez-Gunn and Llamas 2008). This study deals with the estimation and analysis of Spain's water footprint, both from a hydrological and economic perspective. Its ultimate objective is to report on the allocative efficiency of water and economic resources. This analysis can provide a transparent and multidisciplinary framework for informing and optimising water policy decisions, contributing at the same time to the implementation of the EU Water Framework Directive (WFD) (2000/60/EC). It also responds to the current mandate of the Spanish Ministry of Environment and Rural and Marine Affairs, which recently issued instructions for drafting river basin management plans in compliance with the EU Water Framework Directive, with a deadline of end of year 2009 and then every 6 years (BOE 2008).

Integrated water resources management advocates a coordinated approach for managing water resources in a way that balances social and economic needs with concern for the environment. While potentially useful, integrated water management is also controversial. Supporters believe that the multi-dimensional nature of water can only be understood and managed from a holistic perspective, while critics often argue that integrated water management lacks suffi ciently well-defi ned rules for its practical implementation. This book, written by academics, users and practitioners, provides a down-to-earth approach to the ideal of integrated water resources management, drawing from conceptual frameworks and real-life practice to identify the key aspects that are yet to be resolved. As such, it examines the role of water accounting, food trade, environmental externalities and intangible values as key aspects whose consideration may help the water management community move forward. Overall, integrated water resources management is perceived to be a useful utopia, whose value lies more in the steps that need to be taken to make it a reality than in achieving its ever-elusive end goal.

People use lots of water for drinking, cooking and washing, but significantly more for producing things such as food, paper and cotton clothes. The water footprint is an indicator of water use that looks at both direct and indirect water use of a consumer or producer. Indirect use refers to the 'virtual water' embedded in tradable goods and commodities, such as cereals, sugar or cotton. The water footprint of an individual, community or business is defined as the total volume of freshwater that is used to produce the goods and services consumed by the individual or community or produced by the business.

This book offers a complete and up-to-date overview of the global standard on water footprint assessment as developed by the Water Footprint Network. More specifically it:

• provides a comprehensive set of methods for water footprint assessment
• shows how water footprints can be calculated for individual processes and products, as well as for consumers, nations and businesses
• contains detailed worked examples of how to calculate green, blue and grey water footprints
• describes how to assess the sustainability of the aggregated water footprint within a river basin or the water footprint of a specific product
• includes an extensive library of possible measures that can contribute to water footprint reduction.

1.1 General Framework In most arid and semi-arid countries, water resource management is an issue that is both important and controversial. Most water resources experts now acknowledge that water conflicts are not caused by physical scarcity but are mainly due to poor water management (Rosegrant et al. 2002; Benoit and Comeau 2005; Comprehensive Assessment of Water Management in Agriculture 2007; Garrido and Dinar 2010, among others). The scientific and technological advances of the past 50 years have led to new ways to solve many water-related conflicts, often with tools that seemed unthinkable a few decades ago (Llamas 2005; Lopez-Gunn and Llamas 2008). This study deals with the estimation and analysis of Spain's water footprint, both from a hydrological and economic perspective. Its ultimate objective is to report on the allocative efficiency of water and economic resources. This analysis can provide a transparent and multidisciplinary framework for informing and optimising water policy decisions, contributing at the same time to the implementation of the EU Water Framework Directive (WFD) (2000/60/EC). It also responds to the current mandate of the Spanish Ministry of Environment and Rural and Marine Affairs, which recently issued instructions for drafting river basin management plans in compliance with the EU Water Framework Directive, with a deadline of end of year 2009 and then every 6 years (BOE 2008).

Integrated water resources management advocates a coordinated approach for managing water resources in a way that balances social and economic needs with concern for the environment. While potentially useful, integrated water management is also controversial. Supporters believe that the multi-dimensional nature of water can only be understood and managed from a holistic perspective, while critics often argue that integrated water management lacks suffi ciently well-defi ned rules for its practical implementation. This book, written by academics, users and practitioners, provides a down-to-earth approach to the ideal of integrated water resources management, drawing from conceptual frameworks and real-life practice to identify the key aspects that are yet to be resolved. As such, it examines the role of water accounting, food trade, environmental externalities and intangible values as key aspects whose consideration may help the water management community move forward. Overall, integrated water resources management is perceived to be a useful utopia, whose value lies more in the steps that need to be taken to make it a reality than in achieving its ever-elusive end goal.