The relative cost of carbon emissions reductions across regions depends on whether the measure cost by marginal or total cost, private or economy-wide cost, and using market or purchasing power parity exchange rates.

This survey paper examines the problem of achieving global cooperation to reduce greenhouse gas emissions. Contributions to this problem are reviewed from non-cooperative game theory, cooperative game theory, and implementation theory. Solutions to games where players have a continuous choice about how much

China and India have committed to reductions in the emissions intensity of the economy by 40-45% & 20-25% respectively between 2005 and 2020. This analysis looks at how feasible are the proposed reductions in emissions intensity for China and India, and how do they compare with the targeted reductions in the US and the EU.