Climate change is the central global problem of the twenty-first century, and its effects are now being felt throughout the world economy: damage caused by all kinds of extreme weather, droughts, the simultaneous rise in ocean levels and increasing hunger are forcing us to take action. The reduction in greenhouse gases required cannot be tackled by national measures alone and demands a geopolitically coordinated approach. This needs to take into account both the findings of climate science and also economic facts and constraints. In this context, the first step is to present the economic and ecological facts and interrelationships, sector-specific climate risks and approaches to economic solutions.