But other outgrowths of the summit are gaining momentum. The world leaders at Rio who signed the summit's Agenda 21 committed themselves to practical action to improve the global environment. For this to work, local authorities must implement the proposals along with national governments. Accordingly, with the support of Westminster, the Local Government Management Board has asked each British local authority to put in place its own Local Agenda 21 by 1996.
The role of the council is to act as a convenor and a catalyst for change in the local community. 'The whole ethos of Local Agenda 21 is about partnership,' said Anna Dodds, environmental policy officer of Leicester council. 'It's about adopting practices that involve everybody; it's about local democracy - and how this can be brought about.'
Sustainable development was the key phrase at Rio - meaning that each generation should meet its own needs without destroying the ability of future generations to meet theirs. But world leaders also committed themselves to equality of rights, co-operation, education and personal development. And to abide by these principles councils need to adopt decentralised methods of consultation. Local authorities are uniquely placed to bring together interest groups from the private, public, voluntary and education sectors.
Much of the consultation focuses on ways to improve practices in local government, recognising that councils are possibly the most important influence on the local environment. Two out of three of the commitments signed up to at the summit require implementation by local authorities.
Some environmentalists feel for the first time that they are on the same side as their local authority. Paul de Zylva of Croydon Friends of the Earth, which has been involved in developing Croydon's Local Agenda 21, said: 'We have been pushing for this (council contact) for a long time, and then out of Rio came this recommendation that local authorities were a key player in sustainable development.
'Croydon has taken it on with a certain amount of enthusiasm and we are now pushing at an open door. It has set up a Local Agenda 21 sub-committee that reports to the Resources, Finance and Policy Committee. By 1996 they will have in their hands a document which says: 'This is what we need to do to make Croydon sustainable' - although it has to be understood that no London borough can be an island.'
Four working groups have been established in Croydon to consider the natural environment, energy, transport and waste and pollution. Another, on economy and work, will start meeting soon. Membership includes councillors, officials, residents' groups, community and pressure groups, the chamber of commerce and other traders' associations. A surprising amount of consensus is achieved, said Mr de Zylva.
Barbara Wilcox, Local Agenda 21 project coordinator for Croydon council, believes the connection between the working groups and the council's most important committee is vital in ensuring that the group's recommendations are implemented. 'It goes to the heart of the decision making process, which ensures the work is carried forward,' she said.
The initial focus of the working groups is an audit of current practice, examining possible improvements and using the council to test new ideas such as reducing staff travel.
The authority's approach was modelled on that of the Environment Cities. Leicester, the first of these, has contracted out co-ordination of its Agenda 21 consultation to Environ, a charity that emerged from Leicester Environment City. 'Local Agenda 21 is not designed solely for local authorities, it is for communities,' said Ian Roberts, Environ director.
'All sectors must come together to create a more sustainable community. We are not doing this for the councils but in partnership with them. We can involve groups who would find it more difficult to talk to a local authority, and bring in the community perspective.'
Mr Roberts argues that Environ's arms-length relationship with local authorities enables it to maintain a clearer perspective. Environ has also built up what it believes is the country's largest database of good environmental practice, gathered from around the world.
Environ puts problems to specialist working groups that include county and city officials, leaders of the private and voluntary sectors, and academics. The proposals that emerge are given to task forces of council officials to be implemented. Consultations that bring in the public will begin later.
Environ is sponsored by the World Wide Fund for Nature (WWF) which is involved in Local Agenda 21 consultations elsewhere in the UK, such as in Reading where it is working with the council to provide a community consultation model for the implementation of the agenda programme.
'Local Agenda 21 is a heaven-sent mandate for those of us working in communities,' said Ken Webster, senior community education officer for WWF.
The consultations in Reading operate at neighbourhood and street levels, and WWF argues that grass-roots consultation is more likely to change personal behaviour.
'My professional experience is that both 'top down' and 'bottom up' approaches fail,' said Mr Webster. 'It has to be a combination to bring the initiatives together. We work with people to get them to look at their own neighbourhoods and, as the saying goes, to think global, act local.'
WWF is looking to work with other councils, but only where they have twinning links overseas where WWF is also active. From this, the charity wants to build better international environmental networks.
Batley, in Kirklees, has also gone for a community based consultation, as part of its City Challenge scheme. The council believes, though, that this is too time consuming to adopt on an authority wide basis. Initial consultations in Kirklees have already led to new rural footpaths and planned bicycle paths.
Dr Phil Webber, head of the environment unit at Kirklees, fears, however, that authorities may have lost too many of their powers to live up to community expectations. 'If you imagine a city as an organism,' he said, 'then the problem we have is that the brain can't control its own waste.'
He might have added that an incontinent local authority is the stuff of environmentalists' nightmares.