Explore our cities
C40 has 96 member cities
Making up more than 25% of the global economy1
Comprised of 700+ million people2

Declaration Reports

Published February 2022

Since 2017, mayors of world-leading cities have committed to taking urgent climate action by signing C40 declarations. To assess how cities have delivered on their pledges, C40 Cities conducted a thorough reporting process in 2021.

Asian female engineer working on construction site, Hangzhou
© sinology / Getty Images

Sources:
1. 24% of global GDP (2019). Oxford Economics data, C40 modeling & World Bank for global GDP.
2. Oxford Economics data & C40 modelling, April 2021.