• Early climate-related actions should be those with a high local economic and/or environmental payoff per unit of impact on greenhouse gases. • Energy, transport and natural resource management policies can often be better designed to realise greenhouse gas reductions at little or no additional cost. • In energy and transport, investment and network planning need to account for likely future emission constraints in order to avoid costly lock-in effects and premature obsolescence of capital stock. • The local air quality and health benefits of climate policy can be sizeable in the megacities of developing countries, probably exceeding those in OECD countries that have already gone some way to delink carbon emissions from local pollution. • A global market for climate stabilisation services is gradually taking shape in which many developing countries could expect to become net suppliers.