In the global fight against climate change, there has been no shortage of targets and commitments. But people ultimately judge progress by what they experience in their daily lives, and nowhere is the impact of climate action more tangible than in the world’s cities. Mayors understand that the same measures that reduce greenhouse-gas emissions and strengthen climate resilience also improve people’s daily lives. Energy-efficient homes lower bills for families. Increased access to renewables reduces dependence on imported fossil fuels and vulnerability to spikes in oil and gas prices.