C40 Cities Climate Leadership Group
group of cities around the world
C40 Cities (formerly C40 Cities Climate Leadership Group) is a group of 96 cities that represents more than ten percent of the world's population and 23 percent of the global economy. Created and led by cities, C40 is focused on fighting the climate crisis and driving urban action that reduces greenhouse gas emissions and climate risks, while increasing the health, wellbeing and economic opportunities of urban residents.
From 2023, Mayor of London, Sadiq Khan and Mayor of Freetown, Yvonne Aki-Sawyerr serve as C40's Co-Chair, former mayor of New York City Michael Bloomberg as Board President, and Mark Watts as Executive Director. All four work closely with the 13-member steering committee, the Board of Directors and professional staff. The rotating steering committee of C40 mayors provides strategic direction and governance. Steering committee members include: London, Freetown, Melbourne, Jakarta, Abidjan, Phoenix, Medellin, Copenhagen, Nairobi, Tokyo, Curitiba, Boston, Milan, Seoul, Oslo and Hong Kong.
Working across multiple sectors and initiative areas, C40 convenes networks of cities providing a suite of services in support of their efforts, including: direct technical assistance; facilitation of peer-to-peer exchange; and research, knowledge sharing & communications. C40 is also positioning cities as a leading force for climate action around the world, defining and amplifying their call to national governments for greater support and autonomy in creating a sustainable future.
History
C40 started in October 2005 when London Mayor Ken Livingstone convened representatives from 18 megacities to forge an agreement on cooperatively reducing climate pollution and created the 'C20'. In 2006, Mayor Livingstone and the Clinton Climate Initiative (CCI) - led by the efforts of former U.S. President Bill Clinton - combined to strengthen both organizations, bringing the number of cities in the network to 40 and helping to deliver projects and project management for participating cities to further enhance emissions reductions efforts.
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