By the end of 2007, all of the world’s governments should begin negotiations on a climate-change system for the years after 2012, when the current Kyoto Protocol expires. Basic principles should be established during 2008, and by 2009, the world community, including the two largest emitters of carbon dioxide, the US and China, should be ready to make a serious deal, which should be concluded by 2010 and ratified in time to replace the Kyoto Protocol.