There are times when the most difficult decision of all is to acknowledge the obvious.

• It is obvious that the world's national economies are based on the goods and services derived from ecosystems.
• It is also obvious that human life itself depends on the continuing capacity of ecosystems to provide their multitude of benefits.

Yet for too long in both rich and poor nations, development priorities have focused on how much humanity can take from our ecosystems, with little attention to the impact of our actions.

With World Resources 2000-2001, the United Nations Development Programme, the United Nations Environment Programme, the World Bank, and the World Resources Institute reconfirm their commitment to making the viability of the world's ecosystems a critical development priority for the 21st century.

While our dependence on ecosystems may be obvious, the task of integrating considerations of ecosystem capacity into decisions about development is difficult.

• It requires governments and businesses to rethink some basic assumptions about how we measure and plan economic growth.
• Poverty forces many people to jeopardize the ecosystems on which they depend, even when they know that they are cutting timber or extracting fish at unsustainable levels.
• Greed or enterprise, ignorance or inattention also leads people to disregard the natural limits that sustain ecosystems.

The biggest difficulty of all, however, is that people at all levels, from the farmer at the grassroots to the policy maker in the capital, either can't make good use of the knowledge at hand or lack basic information about the condition and long-term prospects of ecosystems. This report, and the Pilot Analysis of Global Ecosystems (PAGE) on which it is based, is a step toward addressing this problem.

In our unique collaboration on the World Resources report series, our four organizations undertook this edition in a genuine partnership to develop recommendations that would safeguard the world's ecosystems. We bring together different perspectives and decades of experience working on environment and development issues. We are motivated by the urgent need for solutions that will benefit both people and ecosystems.

At this moment, in all nations -- rich and poor -- people are experiencing the effects of ecosystem decline in one guise or another: water shortages in the Punjab, India; soil erosion in Tuva, Russia; fish kills off the coast of North Carolina in the United States; landslides on the deforested slopes of Honduras; fires in the disturbed forests of Borneo and Sumatra in Indonesia. The poor, who often depend directly on ecosystems for their livelihoods, suffer most when ecosystems are degraded.

At the same time, people in all parts of the word are working to find solutions: community forest conservation programs in Dhani, India; collective management of grasslands in Mongolia; agricultural transformation in Machakos, Kenya; removal of invasive tree species to protect water resources in South Africa; and restoration of the Everglades in the United States. Governments and private interests at least, stave off the consequences -- and countless billions more may be needed to restore ecosystems on a global scale.

As these examples and many others in this volume demonstrate, our knowledge of ecosystems has increased dramatically, but it has simply not kept pace with our ability to alter them. Unless we use the knowledge we've gained to sustainably develop Earth’s ecosystems, we risk inflicting ever greater, damage on them with dire consequences for economic development and human well-being. Thus, the urgency of this issue: shortsighted, avoidable mistakes can affect the lives of millions of people, now and in the future. We can continue blindly altering Earth's ecosystems, or we can learn to use them more sustainably.

If we choose to continue our current patterns of use, we face almost certain declines in the ability of ecosystems to yield their broad spectrum of benefits -- from clean water to stable climate, fuelwood to food crops, timber to wildlife habitat. We can choose another option, however. It requires reorienting how we ee ecosystems, so that we learn to view their sustainability as essential to our own. Adopting this "ecosystem approach" means we evaluate our decisions on land and resource use in terms of how they affect the capacity of ecosystems to sustain life, not only human well-being but also the health and productive potential of plants, animals, and natural systems. Maintaining this capacity becomes our passkey to human and national development, our hope to end poverty, our safeguard for biodiversity, our passage to a sustainable future.

It's hard, of course, to know what will be truly sustainable in either the physical or political environments of the future. That's why the ecosystem approach emphasizes the need for both good scientific information and sound policies and institutions. On the scientific side, an ecosystem approach should:

• Recognize the "system" in ecosystems, respecting their natural boundaries and managing them holistically rather than sectorally.
• Regularly assess the condition of ecosystems and study the processes that underlie their capacity to sustain life so that we understand the consequences of our choices.

0n the political side, an ecosystem approach should:

• Demonstrate that much can be done to improve ecosystem management by developing wiser policies and more effective institutions to implement them.
• Assemble the information that allows decision makers at all levels to weigh the trade-offs among various ecosystem goods and services and among environmental, political, social, and economic goals.
• Include the public in the management of ecosystems, particularly local communities, whose stake in protecting ecosystems is often greatest.

The goal of this approach is to optimize the array of goods and services ecosystems produce while preserving or increasing both their capacity to produce these things in the future. World Resources 2000-2001advocates an ecosystem approach and recommends how we can apply it.

A critical step in taking care of our ecosystems is taking stock of their condition and their capacity to continue to provide what we need. Yet, there has never been a global assessment of the state of the world's ecosystems. This report starts to address this knowledge gap by presenting results from the Pilot Analysis of Global Ecosystems (PAGE), a new study undertaken to be the foundation for more comprehensive assessment efforts.

What makes the pilot analysis valuable now, before any other assessment, is that it compares information already available on a global scale about the condition of five major classes of ecosystems: agroecosystems, coastal areas, forests, freshwater systems, and grasslands. The pilot analysis examines not only the quantity and quality of outputs but also the biological basis for production, including soil and water condition, biodiversity, and changes in land use over time. And rather than looking just at marketed products, such as food and timber, the pilot analysis evaluates the condition of a broad array of ecosystem goods and services that people rely on but don't buy in the marketplace. The bottom line is a comprehensive evaluation, based on available information, of the current condition of five major ecosystems.

It's an evaluation that clearly shows the strengths and weaknesses of the information at hand. The pilot analysis identifies significant gaps in the data and what it would take to fill those gaps. Satellite imaging and remote sensing, for example, have added to information about certain features of ecosystems, such as their extent, but on-the-ground information for such indicators as freshwater quality and river discharge is less available today than in the past.

Although some data are being created in abundance, the pilot analysis shows that we have not yet succeeded in coordinating our efforts. Scales now diverge, differing measures defy integration, and different information sources may not know of each other's relevant findings.

World Resources report with a conviction that the challenge of managing Earth's ecosystems -- and the consequences of failure -- will increase significantly during the 21st century. We end with a keen awareness that the scientific knowledge and political will required to meet this challenge are often lacking today. To make sound ecosystem management decisions in the 21st century, dramatic changes are needed in the way we use the knowledge and experience at hand, as well as the range of information brought to bear on resource management decisions.

A truly comprehensive and integrated assessment of global ecosystems that goes well beyond our pilot analysis is needed to meet information needs and to catalyze regional and local assessments.

Planning for such a Millennium Ecosystem Assessment is already under way:

• In 1998, representatives from a broad range of international scientific and political bodies began to explore the merits of and to recommend the structure for such an assessment.
• After consulting for a year and considering the preliminary findings in this report, they concluded that a global assessment of the past, present, and future of ecosystems was feasible and urgently needed.
• They urged local, national, and international institutions to support the effort as stakeholders, users, and sources of expertise.

If concluded successfully, the Millennium Ecosystem Assessment will generate new information, integrate current knowledge, develop methodological tools, and increase public understanding. At local, national, and regional scales it will build the capacity to obtain, analyze, and act on improved information. Our institutions are united in supporting this call for the Millennium Ecosystem Assessment.

At the dawn of a new century, we have the ability to change the vital systems of this planet, for better or worse. To change them for the better, we must recognize that the well-being of people and ecosystems is interwoven and that the fabric is fraying. We need to repair it, and we have the tools at hand to do so. What better time than now?

Mark Malloch Brown
Administrator
United Nations Development Programme

Klaus Töpfer
Executive-Director
United Nations Environment Programme

James D. Wolfensohn
President
World Bank

Jonathan Lash
President
World Resources Institute