To be a member of C40, cities must show measurable progress on each of these three missions: cutting emissions by halving fossil fuels by 2030, building resilience, and advancing justice in city climate …

Read through C40’s annual reports, where you’ll find results on emissions, clean air, green jobs, and resilience. Discover plenty of examples of how cities are beating targets, driving real progress, and …

Around the world, C40 mayors and the cities they lead are taking ambitious, collaborative and urgent climate action that aligns with science-backed targets. They work together across borders in order to …

Durante anos 20, C40 defendeu que as cidades são os catalisadores da ação climática. Nossos prefeitos ditam o ritmo da ação climática. Eles entregam resultados concretos e impulsionam …

Durante años 20, C40 ha defendido a las ciudades como catalizadoras de la acción climática. Nuestros alcaldes marcan la pauta en la acción climática. Logran resultados sobre el terreno e impulsan el …

C40 is led by the elected C40 Chair, the Steering Committee and the Board of Directors.

At COP30, C40 Les maires ont démontré les résultats concrets de l'action climatique lorsque les villes ont le pouvoir et les ressources nécessaires pour agir. Par leur action, ils ont démontré ce que …

C40 Une 97 cidades representando 920 milhões de pessoas para combater as alterações climáticas. As cidades são essenciais para agir na velocidade que a crise exige.

What We Do Raising climate ambition Climate action planning C40 Accelerators Inclusive climate action Research and Knowledge Climate Budgeting Programme

Nov 5, 2025 · C40 Cities' triennial climate action conference. The C40 World Mayors Summit 2025 takes place in Rio de Janeiro from 3–5 November.