Climate change is a serious challenge for the international community, including the business community. While some uncertainties remain, applying a risk management perspective to the available information leads us to conclude that a reasonable approach would be for all leaders of business and government to take action now.

This is the consensus view of an unprecedented group of 100 CEOs of major companies, of which we are members, drawn from every industrial sector and region. For the past year, we have worked together under the auspices of the World Economic Forum and World Business Council for Sustainable Development to assemble the most detailed set of guidance yet to emerge from the business community regarding the design of the climate policy framework that will succeed the Kyoto Accord.

Our message to the G8 leaders' meeting in Japan is that nothing less than a new geometry of international cooperation will be required for the international community to achieve the emission reduction goals recommended by the scientific community in an economically efficient fashion.

Where the Kyoto Accord relied almost entirely on a traditional, top-down set of government commitments, we believe the new framework will need to incorporate a more pragmatic and results-oriented mixture of top-down and bottom-up elements aimed at not only increasing the probability that governments will meet their commitments but also enabling them to do so in the least-cost, most pro-growth manner possible.

Above all, the new framework should be designed so that clear and predictable incentives are created to enable obvious economic value to be created over the short and long run from emission reductions. It should facilitate the linkage of explicit or implicit carbon values established at various national and regional levels, with the ultimate aim of establishing a deep and liquid international market for carbon that takes into account international competitive pressures.

It will be necessary for the new framework to respect the prerogative of national governments to employ the domestic policies best suited to their own national circumstances by allowing variation in the magnitude and timing of countries' commitments provided that the overall framework is capable of meeting specific intermediate and long-term environmental goals.

In line with the latest assessment of the Intergovernmental Panel on Climate Change (IPCC), we urge governments to seek consensus on a long-term goal of at least halving global emissions against current levels by 2050.