The ecosystem setting of both agriculture and water provides a conceptual framework for managing the needs of agriculture for water and the impacts of water upon agriculture. Water underpins all benefi ts (ecosystem services) that ecosystems provide, including all agricultural production. The availability of water, in terms of both its quantity and quality, is also infl uenced heavily by ecosystem functioning. Understanding this relationship of water, ecosystems and their services with agriculture is at the heart of understanding, and therefore managing, water and food security. There are opportunities to move beyond seeing the agriculture-ecosystem-water interface as one of confl ict and trade-offs, towards simultaneously achieving both increases in sustainable food production and improvements in the delivery of other ecosystem benefi ts by agriculture through more widespread adoption of ecosystem-based solutions. These concepts and approaches are explained briefl y here as an introduction to understanding the interlinkages between ecosystem services, water and food security in subsequent chapters of the book. *

Various food and fi nancial crises have increased the pressure on natural resources while expanding on alternative ways of considering agroecosystems as potential long-term providers of ecosystem services if managed in a sustainable and equitable way. Through the study of interrelations between ecosystems, water and food security, this book has aimed to increase the understanding and knowledge of these interactions for better planning and decision making processes at various levels. This chapter concludes Managing Water and Agroecosystems for

The integrated role of water in ecosystems and, in particular, in agroecosystems, as well as the multiple uses of water -across various sectors that have increasing demands, have been widely recognized. But regions and institutions are still struggling to resolve issues around water -be it scarcity, accessibility or degradation. Mostly, they are caught in conventional institutional and policy frameworks that have been set up based more on sectoral than on cross-sectoral principles, thus preventing them from achieving the ultimate goal of sustainability. This chapter analyses the current and future challenges related to water availability and water use for agriculture from this perspective. It looks at water quantity and quality, water infrastructure, and related governance and institutional aspects, using case studies from basins in different geographic regions.