The United Nations Conference on Environment and Development (UNCED or the "Earth Summit") in Rio de Janeiro in June 1992 was the largest and most complex conference ever organised by the UN. It was attended by 178 governments, and there were some 120 Heads of State at the Summit that concluded the conference. The preparatory process had taken two and a half years and generated floods of words and reams of paper. The event had extensive press coverage. Debates on how to follow up the conference outcome are in progress all over the world.

The outcome of a conference should be judged against its stated objectives. The mandate for the UN Conference on Environment and Development (UNCED), more popularly known as the Earth Summit, was established by the UN General Assembly resolution 44/228 of December 1989, a very wide-ranging document that raised an array of complex environment and development issues.

On many of these issues there is little scientific, let alone political, consensus: for example "the relationship between environmental degradation and the structure of the international economic environment". The resolution uses language that later came to haunt the negotiating process. For example, it talks about the need to identify "new and additional financial resources" for developing countries and also about transfer of "environmentally sound technologies" on "concessional and preferential terms" to these countries.

The resolution also calls for "specific agreements and commitments by Governments for defined activities to deal with major environmental issues", allowing for many different interpretations. It may be argued that the resolution establishing UNCED did not set a very workable mandate for the conference.

Later in the planning process, the UNCED Secretary-General, Maurice Strong, presented to the second Preparatory Committee (Prepcom 2) in March/April 1991 operational guidelines for the meeting. He listed the "potential outputs of the conference" as follows:

It is easy to agree with Strong when at UNCED's closing session he expressed his disappointment with the political commitment shown by some of the 178 nations attending. In fact, the immediate conference result falls well short of his stated intentions. It represents the lowest common denominator of national interests, the inevitable effect of the UN insistence on consensus.

The treaty on climate change was weakened by US refusal to allow timetables and targets for reductions of greenhouse gas emissions. The biodiversity treaty was also weakened by the United States, which ended up not signing, largely because it felt that the treaty compromised its biotechnology industry. The statement on forest principles makes many useful points about forest management; but it is non-binding, and it is not clear what attention governments will pay to it.

The action programme, Agenda 21, covers almost every conceivable issue related to sustainable development. It contains many useful ideas. But if it is to be of practical use, the most important elements must be separated out and translated into operational plans at national and international level. It remains largely unfinanced, since the rich countries only agreed to meet a small fraction of the estimated cost of its recommendations.

The "Rio Declaration" was heavily compromised during negotiations. Rather than the punchy ten commandments-type statement originally envisaged for the Earth Charter, it became a bland declaration that provides something for everybody. The Commission on Sustainable Development, upon which UNCED agreed, is potentially one of the most important institutions established by the conference. It provides a mechanism whereby the World Bank and similar institutions, as well as national governments, can be held responsible for any failure to live up to the precepts of sustainable development.

Though these immediate results of UNCED fall short of stated intentions, it would be wrong, indeed arrogant, to judge this huge conference only in the light of its short-term achievements. It has been a momentous exercise in awareness-raising at the highest political level. No leading politician can any longer claim ignorance of environment and development linkages. It is therefore quite conceivable that future international debates on issues related to these issues will be more enlightened and move forward faster.

Indeed, it is difficult to escape the conclusion that the conference has set in motion some very large, if slow moving, wheels. moving long- term processes for dealing with two of the most pressing and complex global environmental concerns of the day.