10 Defining Moments in C40 History

2015 marks the 10-year anniversary of C40 Cities Climate Leadership Group. To celebrate these 10 Years of Results, we will be sharing our favorite lists of 10 throughout the year.

1. The Organization is Founded

In October 2005, then Mayor of London Ken Livingstone convened representatives from 18 megacities to forge an agreement on cooperatively reducing climate pollution. This agreement represents the launch of C40.

2. And Then We Were 40

By 2006, we had grown to 40 cities, and thus the name C40 was born. That year, Mayor Livingstone invited President Clinton’s Climate Initiative (CCI) to become our implementing partner on world-class carbon reduction projects -- a partnership Mayor Miller of Toronto took forward when he became C40 Chair in 2008.  

3. Mayors Collaborate

In 2007, New York City Mayor Michael R. Bloomberg hosted the second C40 Summit, bringing together 36 mayors from major global cities. Through a comprehensive program of interactive sessions, delegates shared best practices and identified collaborative projects all aimed at tacking climate change.

4.  A Landmark Merger

C40 took the climate community by storm with the 2011 announcement of a formal merger between C40 and CCI’s Cities Program, forged by President Clinton and then Mayor of New York City and C40 Chair, Michael R. Bloomberg, bringing significant resources and infrastructure to create a preeminent global climate action organization.

5. Social & Digital Debut

In 2011, C40 entered the global climate conversation with the launch of its C40 and National Geographic blogs, Twitter and Facebook channels.  Today, there are myriad ways to connect with C40, the go-to place for news and insight on global cities taking climate action.

6. A Network of Networks

Connecting cities on topics of common interest became the organizing principal of the C40 in 2012. We now have more than 15 active working groups of global cities focused on critical issues including bus rapid transit and building energy efficiency.

7. Evidence is King

In February 2014, C40 Chair Mayor Paes unveiled the second edition of our Climate Action in Megacities report, showing action had doubled in two years among C40 members and establishing unequivocally the leadership role of cities on the world stage.  This flagship research series provides a catalogue of city climate actions and mayoral powers across key sectors.

8. Nations Take Note

C40 is forging a new era of partnership between cities and national governments, most recently helping to launch a global Compact of Mayors, the world’s largest cooperative effort of cities to fight climate change. Announced at UN Climate Summit in New York, the compact allows cities to contribute to strong, transparent and credible national GHG targets in the run up to Paris COP 21 and beyond.

9. On-the-Ground Support

In 2014, C40 launched a new programme to provide direct support to selected cities through a competitive application process. City Advisers are awarded to cities with the greatest potential to develop impactful climate initiatives, making gains that would otherwise not be possible.  To date, City Advisers have been awarded to ten member cities. 

10. A Fully Global Alliance

At C40 2014 Mayors Summit in Johannesburg, Mayor Paes became the first C40 chair from the Southern Hemisphere. Later that year, C40 welcomed Tshwane as its 70th member city – implementing a growth strategy that includes key megacities in Africa, China and India.