urban cooling solutions can be deployed in the short term to help mitigate the risk of rising urban air temperatures. This primer and its appendix, Cool City Case Studies: Reducing urban Heat, provide practical, actionable guidance and examples for implementers, policy makers, and planners tasked with mitigating urban heat impacts. The report covers: - the challenges of rising temperatures for cities, and for urban design more broadly; - actions and solutions that can be deployed at the building, community, and city levels to reduce excess heat and promote thermal comfort; - the benefits of an integrated deployment of urban cooling solutions at scale; - a framework for an inclusive process to develop urban cooling strategies; - the benefits of heat action plans to protect residents from periods of extreme temperatures; - examples, results, and recommendations from urban cooling policies and actions implemented around the world.