Sustainability - Local Issues

California's is by far the most comprehensive state system being instituted, and cap-and-trade is to begin in the state in 2012. Indeed, Mary Nichols, chairwoman of the California Air Resources Board, the regulator responsible for implementing cap-and-trade, calls it the "capstone of our climate policy".

But it is not the first state system to move on cap-and-trade.

Ten north-eastern and mid-Atlantic states capped and began reducing carbon dioxide emissions in January 2009. That Regional Greenhouse Gas Initiative is working to reduce CO2 emissions from the power sector 10 per cent by 2018.