THIS VOLUME WAS prepared by the Conditions and Trends Working Group of the Millennium Ecosystem Assessment. The Millennium Ecosystem Assessment is an international work programme designed to meet the needs of decision makers and the public for scientific information concerning the consequences of ecosystem change for human well-being, and options for responding to those changes. It focuses on ecosystem services (the benefits people obtain from ecosystems), how changes in these ecosystem services have affected human well-being, how ecosystem changes may affect people in future decades, and response options that might be adopted at local, national or global scales to improve ecosystem management and thereby contribute to human well-being and poverty alleviation. More than 1,300 authors from 95 countries have been involved in four expert working groups preparing the global assessment, and hundreds more are undertaking more than 20 sub-global assessments.

This volume consists of an executive summary, and is then divided into four parts. Within Part I on General Concepts and Analytical Approaches, Chapter 1 provides the conceptual framework, while Chapter 2 looks at the analytical approaches to the global assessment of ecosystems and ecosystem services. Chapter 3 summarizes the most important changes in key direct and indirect drivers of ecosystem changes over the last part of the twentieth century, and considers some of the key interactions between them. The chapters that follow are on biodiversity, ecosystem conditions and human well-being, and vulnerable people and places, and are discussed on a global scale. Part II is an assessment of 11 groups of ecosystem services, each with their own chapter. Four concern provisioning services (fresh water, food, timber/fibre/fuel, and new products and industries from biodiversity); six discuss regulating and supporting services (for instance, nutrient recycling and climate and air quality) and one is cultural (cultural and amenity services). These chapters also give examples of the responses of decision makers at various levels to issues relating to changes in service supply.

Part III assesses the systems from which ecosystem services are derived, with chapters on marine fisheries, coasts, inland water, forests and woodland, drylands, islands, mountains, polar systems, cultivated systems and urban systems. The final chapter seeks to bring together the key themes with an integrated narrative, tracing the principal causes of ecosystem change, the consequences for ecosystems and ecosystem services, the impacts on human well-being and implications for the future. As with the reports of the Inter-Governmental Panel on Climate Change, many authors contribute to most of the chapters – with coordinating lead authors, lead authors, contributing authors and review editors. So this represents a tremendous work of synthesis, drawing together the knowledge of hundreds of specialists. Supporting material for many of the chapters and for other aspects of the Millennium Ecosystem Assessment (this volume is produced by one of four working groups) can be found at www.millenniumassessment.org/ [1]