<P>No one can be certain about the potential costs of failing to combat manmade climate change. But there is general agreement that lack of action could have significant implications for the world economy, especially in developing countries. The risk of unpredictable, irreversible damages worldwide is significant. Considering the costs and risks of inaction, ambitious attempts to reduce greenhouse gas emissions are economically rational. In that spirit, the leading industrial countries have begun negotiating the main elements of a post-2012 international framework for addressing climate change.</P><P>Success in abating world emissions will ultimately require a cost-effective set of policy instruments that is applied as widely as possible across all public and private sources of greenhouse gases. The volume explores feasible ways to meet these requirements for successful post-2012 international climate policies.</P>