The C40 is a group of the world’s largest cities committed to tackling climate change.

C40 Large Cities Climate Leadership Group

Cities consume 75 per cent of the world’s energy and produce 80 per cent of its greenhouse gas emissions. That is why working together is so important and will help deliver emissions reductions and better energy efficiency.

Mayors of large cities are uniquely positioned to take action on climate change. Some cities have developed best practices in reducing emissions from transportation, heating, and buildings, and also in developing low carbon energy supply.

In August 2006 the Mayor signed a partnership agreement between the Large Cities and the William J. Clinton Foundation, headed by former US President Bill Clinton. The Clinton Climate Initiative has agreed to service the C40 by working with cities on carbon-reduction programmes.

Building on the first large cities climate summit hosted by the Mayor of London in October 2005, the C40 cities will meet again in New York in May 2007.

The C40 Large Cities to date are:
Bangkok, Berlin, Bogotá, Buenos Aires, Cairo, Caracas, Chicago, Delhi NCT, Dhaka, Houston, Istanbul, Jakarta, Johannesburg, London, Los Angeles, Madrid, Melbourne, Mexico City, Moscow, New York, Paris, Philadelphia, Rome, Sao Paulo, Seoul, Tokyo, and Toronto.

Affiliated C40 Cities are:
Austin, Barcelona, Copenhagen, Curitiba, Heidelberg, New Orleans, Portland, Rotterdam, Salt Lake City, San Francisco, Seattle, and Stockholm.