Climate change is a matter of extreme urgency. Integrating science and economics, this book demonstrates the need for measures to put a strict lid on cumulative carbon emissions and shows how to implement them. Using the carbon budget framework, it reveals the shortcomings of current policies and the debates around them, such as the popular enthusiasm for individual solutions and the fruitless search for 'optimal' regulation by economists and other specialists. On the political front, it explains why business opposition to the policies we need goes well beyond the fossil fuel industry, requiring a more radical rebalancing of power. This wide-ranging study goes against the most prevalent approaches in mainstream economics, which argue that we can tackle climate change while causing minimal disruption to the global economy. The author argues that this view is not only impossible, but also dangerously complacent.