Cities and urban regions occupy just 0.12% of the Earth's surface but are home to 50% of the population and account for 75% of energy consumption and CO2 emissions. By 2050, the world will need to build urban infrastructure equivalent to what was built in the last 4,000 years to accommodate population growth. Local governments and cities will be critical to addressing global challenges like climate change and urbanization, as they are on the front lines and their actions can have widespread impact. ICLEI, an international organization for local governments, works to support cities in transitioning to low-carbon and climate-resilient development through initiatives, events, and tools to share solutions and accelerate climate action.