have grown up around the world over the last decade that have succeeded in putting sustainability issues on the global political agenda and in beginning the difficult process of translating this global interest into practices that will actually work in local and regional circumstances. Although humanity's common journey toward sustainability has not been charted with a discernible endpoint, the journey has already begun.
The reconciliation of society's developmental goals with the planet's environmental limits over the long term is the foundation of an idea known as sustainable development. This idea emerged in the early 1980s from scientific perspectives on the interdependence of society and environment, and has evolved since in tandem with significant advances in our understanding of this interdependence. During the concept's first decade, it garnered increasing political attention and acceptance around the worldmost notably through the activities of the Brundtland Commission (1983–1987) and the United Nations Conference on Environment and Development, held in Rio de Janeiro in 1992.
As the 20th century draws to a close, however, the difficulties of actually delivering on the hopes that people around the world have attached to the idea of sustainable development have become increasingly evident. In part, these difficulties reflect political problems, grounded in questions of financial resources, equity, and the competition of other issues for the attention of decision makers. In part, they reflect differing views about what should be developed, what should be sustained, and over what period. Additionally, however, the political impetus that carried the idea of sustainable development so far and so quickly in public forums has also increasingly distanced it from its scientific and technological base. As a result, even when the political will necessary for sustainable development has been present, the knowledge and know-how to make some headway often have not.
This study, conducted by the National Research Council's Board on Sustainable Development, is an attempt to reinvigorate the essential strategic connections between scientific research, technological development, and societies' efforts to achieve environmentally sustainable improvements in human well-being. To that end, the Board seeks to illuminate critical challenges and opportunities that might be encountered in serious efforts to pursue goals of sustainable development.
Of course, which goals should be pursued is a normative question, not a scientific one. Our analysis, therefore, is based on goals for human well-being and environmental preservation that have been defined through recent extensive and iterative processes of international political debate and action, and sanctioned at intergovernmental conferences over the last several decades. (These goals are reviewed in some detail below.) Our choice of goals could have been different, and the goals actually pursued