Your comprehensive resource for urban climate solutions
Cities are vital implementers of climate action and all cities, of every size and in every country, matter. The C40 Knowledge Hub exists to help cities succeed by making the insight and advice of leading cities accessible to all.
It’s the most comprehensive resource currently available on city climate action: covering tried-and-tested solutions and emerging ideas across every sector, with practical guidance on what these are, how to deliver them, and examples from cities already doing it.
Explore practical guidance on climate solutions
You’ll find different types of content depending on what you need:
- Policy briefs: The essential evidence and arguments on key sectors and actions, as well as issues that are frequently misunderstood.
- Implementation guides: ‘How to’ guides on designing and delivering climate solutions, covering steps and considerations, common challenges and ways that cities have overcome them.
- Data explorers: Transparent data portals providing context and benchmarking mechanisms.
- Case studies and good practice examples: Policy explorers and deep dive case studies explaining what cities have achieved, how they did it, and what other cities can learn.
- Commentary and opinion: Hear directly from city policymakers and other experts.
Entry points for every stage of climate action
Understanding the fundamentals
I need to understand the basics of city climate action
Start with Introducing urban climate action: What, why and how. This one-stop guide gathers the basics in one place: why it matters, the targets we need, the key sectors to prioritise. It sets outproven approaches to cut emissions, adapt to climate change and maximise the benefits.
I need to explain why city-level climate action matters
Why city action is critical in the fight against climate change sets out the foundational case for cities: why every city faces climate impacts, why they are uniquely positioned to act, and how local leadership drives global progress.
Building the case
I need to build the case for why our city should act
Policy briefs offer concise, evidence-based summaries that explain why specific actions and investments matter and how to make the case for them. Use them to prepare leadership briefings, build a business case for a specific investment, or respond to pushback and criticism with solid data.
Finding solutions, planning and implementation
I need to plan our city’s approach
Start by developing a climate action plan. Build the evidence base and design a plan that responds to your city’s main sources of emissions, climate risks and wider needs.
I need to deliver a specific solution
Use Implementation Guides for advice on policy approaches and trade-offs. Filter by sector to find practical step-by-step guidance, covering design considerations, common challenges, and how cities have overcome them.
I need to understand funding and financing options
Browse Finance and Economics for funding and financing strategies. Many implementation guides also set out financing options for the specific sector or action.
Learning from leading cities
I need data to benchmark our progress
Access transparent data and analysis to understand how your city compares, where progress is being made, and what gaps remain. Data insights provide benchmarking dashboards and indicators, while research reports offer comparative analysis across cities and regions.
I need to see what leading cities are doing
Explore real-world examples of how cities are delivering climate action in practice. Case studies and best practice examples show what cities achieved, the policies and programmes they used, and the lessons others can apply.
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