As we approach the UN climate Change Conference, COP21, in Paris this December, the focus will be on national governments to reach a binding global climate deal. But Cities100 is here to remind us that city leaders are not waiting for national level changes. Instead, they are leading the charge against climate change by implementing local solutions to global problems. As the global discussion on climate change intensifies, cities are leading the way to a sustainable future. And for good reason. By 2050, nearly 70% of the world’s population will live in a city. As urban societies continue to expand and change, so too do the challenges facing them, particularly when it comes to climate change. This growing urban population is vulnerable to the impacts of climate change – for example, 90% of all urban areas are coastal – but it is also powerful.