Dec 2013 – Jun 2019

C40 Cities Climate Leadership Group



Multiple countries – Global

To demonstrate that tackling climate change is both feasible and beneficial for cities.

$9,640,000 Grant Value

$119,885 evaluation budget



Other funders

  • Bloomberg Philanthropies -

  • Realdania

Cities are at the forefront of the fight against climate change: around 70% of global energy is consumed in cities, leading to a similar share of global CO2 emissions being emitted in cities. 

This means that rapid climate action at city level is needed to constrain demand for energy through the deployment of cleaner policies and infrastructure in various sectors such as transport, planning, waste, etc. 

Fortunately, cities have often demonstrated a high level of ambition and have helped lead the way to support the transition to a low carbon economy. In some cases, this has meant that cities have acted first, with national governments following this leadership. Being responsible for the daily lives of city residents has helped many officials and mayors to understand that providing a climate-safe future promises multiple benefits - such as cleaner air, sustainable jobs and energy security. 

Click here to learn about the role cities can play in the fight against climate change. 

However, cities’ commitments to act need to be strengthened and supported by civil society. They need to have access to the tools, guidance and international best practice examples that will help them to implement the most ambitious climate actions. Moreover, continued effort is needed to tackle barriers to city delivery such as access to finance, lack of adequate decentralisation of power from national governments or weak partnerships with the private sector.

To address these challenges, CIFF decided to renew its support to C40 in its fight against climate change for another three years. C40 is a network of 90 of the world’s megacities committed to addressing climate change. Together the C40 network accounts for over half a billion city residents from all continents, with a balanced representation of Global North and Global South cities. Now established as one of the main platforms for cities who want to tackle climate change, C40 is a data driven, best practice network aiming to catalyse ambition and support better and faster implementation.

C40 does this by:

  • Connecting cities to promote the dissemination, replication and scale-up of best practice solutions
  • The provision of technical assistance and research to identify and implement key abatement opportunities
  • The promotion of consistent emissions measurement and performance reporting, which allow greater transparency on cities' efforts to mitigate climate change.

C40 also engages in international forums to amplify the voice of its members, showcase their successes and push for more ambition from other stakeholders.


This investment aims to contribute to C40 cities' achieving 1.3 billion tonnes of carbon dioxide equivalent of cumulative mitigation potential by 2030, and by providing a platform for the global leverage and replication of best practice climate-smart principles. With CIFF's support. C40 has played a significant role in increasing the visibility and credibility of cities taking the lead on climate mitigation, deploying policies, strategies, and approaches that embed this into city governance and administration.

Reducing emissions by 1.3 billion tonnes of CO2 is like taking every vehicle in the US off the road for one year

As a platform, it has been successful in motivating mayors through peer-to-peer pressure and in providing the relevant support at the technical level to implement commitments. The research produced by C40 staff has influenced the way cities’ role in fighting climate change is understood. This has helped to establish C40 as one of the key on-state actor voices in the run-up to COP21, playing a critical role in raising ambition and securing an ambitious Paris Agreement.

An evaluation, led by Ramboll, has been finalised (you can download the full report below). 

C40 is overall deemed by the member cities as an effective and impartial resource for advice, and the support delivered by the C40 organisation is considered of very high quality. The evaluation found that C40 membership and the network’s activities clearly contribute to better implementation of climate action through sharing of good practices, experiences and knowledge between member cities, at both the political and the technical level. 

C40 has been particularly successful in creating a political platform which motivates mayors, and participation is a co-driving effect creating momentum for climate action in the member cities. 

The work on measurements has influenced norm, standards and ways of measuring city emissions, with C40 strongly promoting and supporting implementation of the Global Protocol for Community-scale GHG Emission Inventories (GPC tool). 

However, direct links between C40 support and tangible climate action leading to CO2 reduction was not possible to establish in the evaluation, as actual implementation and investment decisions are determined by several other factors, such as access to finance, political priorities and development needs. 

Click here to download the full report (PDF).