Regulation, carbon taxes and carbon trading are recommended to reduce greenhouse gas emissions. It is argued that the world economy can lower its greenhouse gas emissions at a significant but manageable cost. The review concludes that immediate reductions of greenhouse gas emissions are necessary to reduce the worst risks of climate change. The review's conclusions were widely reported in the press. Stern's relatively large cost estimates of 'business-as-usual' climate change damages received particular attention. These are the estimated damages that might occur should no further effort be made to cut greenhouse gas emissions.