The increasing frequency, intensity, and duration of heat waves due to climate change have escalated the occurrence of extreme heat risks, raising significant concerns in many cities. The unequal distribution of heat exposure and the effects within cities compound these concerns as certain neighborhoods consistently experience higher temperatures, disproportionately affecting vulnerable groups such as low-income, elderly, and minority populations. The city of Phoenix, Arizona, epitomizes these challenges and the innovations in the institutions, planning, and policies needed to address them. The rapidly growing city recorded 31 consecutive days over 110°F (43.3°C) in 2023 and a record number of heat-related deaths. The city also established the first publicly funded city office specifically tasked with comprehensively addressing extreme heat, which presents a unique opportunity to analyze a novel model for heat governance. This case study explores how the City of Phoenix governs extreme heat, partners with universities and other levels of government, and develops new heat plans, policies, and programs.