At the 24th United Nations Convention on Climate Change in Katowice, Poland, in December, a consultation of scientists, city practitioners and NGOs responded to the IPCC 1.5 Special Report with a stark question: What does it mean for cities to limit global warming to 1.5 degrees Celsius in just over a decade? The 9,176 cities committed to the Global Covenant of Mayors for Climate & Energy are on the vanguard of efforts to mitigate and reverse the effects of climate change — and, through joint efforts like from Seoul, South Korea, Chefchaouen, Morocco and Edmonton, Canada who are already acting as key drivers of this vital mission.