This case study series features key findings from the 4.5-year-long Ambitious City Promises Project (ACP) that co-created climate action policies in Southeast Asian megacities with local stakeholders. Three core principles guided ACP’s efforts: Inclusion, Exchange, and Action. This case study encapsulates Pasig City’s ambitious climate actions towards becoming “a model community of empowered citizens with high quality of life.” It details the formulation process for the Promise of Pasig ‒ the city’s climate declaration ‒ as well as implementation mechanisms and paths forward to successfully deliver the sector-specific goals aggregated within the Promise of Pasig. This commitment has now been formally integrated into Pasig City’s climate action policies.