The world has just marked the 20th anniversary of the United Nations Conference on Environment and Development held in Rio de Janeiro, Brazil. Ambitions were high at the Earth Summit in Rio 20 years ago as I can attest. The world was riding a wave of optimism that nations could find the ways and means to tackle the global environmental threats facing mankind. The Framework Convention on Climate Change was inaugurated, which set the goal of avoiding dangerous anthropocentric interference with the climate system, and launched the quest for effective implementing systems.

We have learned a few things in those intervening 20 years. One of the lessons is that the good wishes of international negotiators and the good offices of national governments have not been sufficient to slow the growth of greenhouse gas emissions. And an agreement on the details has been much harder to achieve than anticipated. Another lesson is that civil society can make a huge difference in actual outcomes irrespective of treaties or protocols.

Let me give you some examples. Seven years ago the Chinese Association for Non-governmental Organization Cooperation mounted a campaign to get major energy users, such as office buildings and hotels, to voluntarily agree to limit their summertime thermostats to 26 C. The concept was simple, yet powerful: Cut the excessive use of air conditioning, save electricity, save emissions, and save money. The national government in 2006 introduced regulations, which set government thermostats at the same 26 C minimum.

The next year, the Chinese Association for Non-governmental Organization Cooperation and the US-based Environmental Defense Fund launched a green commuting campaign to reduce both congestion and emissions from Beijing's clogged roads. Employers throughout the city signed pledges to develop employee commuting programs. Designed initially to help improve Beijing's air quality for the Olympics, the concept has been deployed at every major national event since. We took the concept beyond local air quality by measuring the resulting greenhouse savings.

These are the kinds of social and economic interventions that need to be conceived, tested, multiplied and leveraged throughout the world if we are to meet the challenge of sustainability. By some lights, Rio+20 underscored what has not happened rather than what has. However harshly we grade our collective performance, Rio's intense environmental focus did spawn a corresponding serious focus on Agenda 21 in China. In fact, July 22 marks the 20th anniversary of the founding of the China Association for Non-governmental Organization Cooperation, one of China's many responses to Rio.

Increasingly, the government has become aware that it cannot solve all the problems confronting China and that the energies of civil society mobilized and focused through non-governmental organizations is a powerful force for good that can effectively augment the government's resources. A number of immediate opportunities present themselves.

China is embarking on a number of new directions in environmental policy to harness market forces that could benefit from NGO participation.

Since using markets to solve environmental problems is not an obvious strategy, its success requires substantial capacity building, a task at which NGOs excel. NGOs can help build up the environmental infrastructure necessary to successfully harness these new environmental markets. This infrastructure includes developing the methodologies for monitoring and reporting both emissions and reductions. This opportunity was just opened up by the issuance of a voluntary emission reduction regulation by the National Development and Reform Commission.

Testing these methodologies in the field and building up experience through learning-by-doing will help establish both the credibility of proposed measures as well as ensuring that they can be practically deployed. In order for markets to succeed, the transactions costs associated with producing, marketing, verifying, registering, and selling emissions reductions need to be minimized so that the benefit to buyers and sellers is maximized. NGOs with their not-for-profit mission are ideally suited to the challenge of grinding these costs down while preserving core environmental integrity.

Even after the approval of methodologies, there will be a substantial need for verification services so that both buyers and the government are confident that the claims of sellers are met. NGOs can play a big part in helping to build up the necessary human capital through targeted training programs ultimately leading to licensing. This type of third party verification has been a key ingredient in the success of these markets elsewhere. Carbon market services are an emerging new industry.

Carbon markets are built on the same foundation that has powered the dramatic reform and opening-up over the last 30 years in China. One of the hallmarks of this success has been the opportunity to tap opportunities wherever they can be found. Carbon markets will open up the same space for environmental entrepreneurs. For example, Environmental Defense Fund in partnership with the State Council's poverty alleviation office has been linking greenhouse reduction with poverty reduction by helping farmers to change production practices to improve efficiency.

These are examples of how civil society can be engaged in the business of helping to construct effective environmental management systems in China. It is critical for China and the world that these new policy experiments succeed. At a time when the economic slowdown is forcing governments and businesses to review all expenditures more carefully, marshaling all available resources to propel environmental progress is in all of our interests. While government must set the rules of the game and businesses must meet the new requirements, NGOs can help all parties by bringing new creative energies to bear. We need all of the help we can get if the next 20 years of environmental progress are to be different from the last.

The author is vice-president of the Environmental Defense Fund.