Institutions matter because they are instrumental in systematically adapting to global climate change, reducing disaster risks, and building resilience. Without institutionalised action, adapting to climatic change remains ad-hoc. Using exploratory research design and longitudinal observations, this research investigates how urban stakeholders and policy entrepreneurs negotiate institutional architecture and pathways for sustaining climate change adaptation and resilience implementation. This paper introduces hybrid institutionalism as a framework to understand how city administrators, local policy makers, and policy advocates navigate complex institutional landscapes that are characterised by volatility and uncertainties. Grounded in the experience from a recent experiment in Indonesia, this research suggests that institutionalisation of adaptation and resilience agenda involves different forms of institutionalisation and institutionalism through time. Future continuity of adaptation to climate change action depends on the dynamic nature of the institutionalism that leads to uncertainty in mainstreaming risk reduction. However, this research found that pathway-dependency theory emerges as a better predictor for institutionalising climate change adaptation and resilience in Indonesia.