C40 is a network of the world’s megacities committed to addressing climate change. C40 supports cities to collaborate effectively, share knowledge and drive meaningful, measurable and sustainable action on climate change. Working with P4G, C40 ensures city solutions have clear climate action plans. C40 is involved with P4G partnerships on sustainable transportation, clean energy, and efficient buildings. C40 also partners to host key events such as the 2018 Global Climate Action Summit in San Francisco.