So far the effort to tackle global warming has achieved little. Copenhagen offers the chance to do better...

Also in this special report:

Is it worth it?: What economists have to say about mitigating climate change.

The green slump: Why investors have been deserting clean
energy.

Good policy, and bad: Some mitigation policies are e…ffective, some are effiˆcient, and some are neither.

Vampires on a diet: How a boring gadget saved $2 billion worth of electricity.

Cap and tirade: America struggles with climate-change
legislation.

Who cares?: Don't count on public opinion to support
mitigation.

A long game: China sees opportunities as well as dangers
in climate change

Closing the gaps: How the world divides on a global deal.

What needs to change: The prospects are gloomy, but they can be made brighter.

Unpacking the problem: The attractions of a piecemeal approach to global warming.