On September 21, an estimated 400,000 people gathered in New York City for the People’s Climate March to demand bold action on climate change. The march was timed to coincide with the UN Climate Summit, the first meeting of world leaders in five years to discuss the global response to climate change. The import of the march lay not in its immediate impact on the Summit (the real show will be in Paris next year), but in the invigoration of a diverse climate movement. Over 1,500 organizations—from environmental, labor, faith, and social justice communities—came together under a common banner, the political expression of the ecological reality that climate change affects everyone. Climate marches were organized simultaneously in 100 cities across the globe. Although this is not the fully formed global citizens movement able to effect wide-reaching change, it shows a powerful stirring in the grassroots for such a movement.