C40 Cities

C40 is a global network of nearly 100 mayors of the world’s leading cities that are united in action to confront the climate crisis.

Mayors of C40 cities are committed to using an inclusive, science-based and collaborative approach to cut their fair share of emissions in half by 2030, help the world limit global heating to 1.5°C, and build healthy, equitable and resilient communities. C40 supports mayors to do this by:

• Raising climate ambition through 1.5°C climate action plan support, high-impact accelerators and fostering innovation.
• Building equitable and thriving communities via global and regional programmes.
• Building a global movement through robust international advocacy and diplomacy.
• Scaling up climate action and sharing best practices across high-impact sectors.
• Facilitating access to finance for investment in green jobs and projects that improve resilience in cities.

Carbon-intensive advertising webinar

In April 2023, C40 Cities hosted a webinar called 'What can cities do about high-carbon advertising?', with contributions from C40, Global Climate and Health Alliance, Badvertising, Adfree Cities, CAPE, Reclame Fossielvrij and the Haarlem City Council. An article summarizing the webinar, as well as the full slides and webinar recordings can be found here.

Comprehensive implementation guide

In November 2024, C40 Cities published the webpage 'How cities can restrict carbon-intensive advertising', collecting argumentation, model motion texts and relevant discussions and lessons learned from the cities that already banned fossil ads. Their comprehensive implementation guide can be found here.