"If you change your city, you're changing the world," says Eric Garcetti, mayor of Los Angeles and chair of C40 Cities, a network of the world's megacities committed to tackling the climate crisis. He shares tangible ways Los Angeles and other cities across the globe are promoting economic and social justice while taking concrete action on climate change -- and talks about how to create a more inclusive, green and sustainable society as we rebuild from COVID-19. (This virtual conversation, hosted by TED's current affairs curator Whitney Pennington Rodgers, was recorded July 7, 2020.)