Public participation plays an important role in the development of rapid response services to support the sustainability of Jakarta Smart City. This study aims to explore and analyse the level of public participation in utilising and developing these services, and their impact on urban sustainability. The research method used is a qualitative case study through in-depth interviews and document analysis. The results of the study indicate that the level of public participation in rapid response services in Jakarta Smart City varies greatly. Factors such as accessibility, trust, and awareness are the main determinants of the level of public participation. Citizens who actively participate tend to feel greater benefits from these services, while those who are inactive tend to experience gaps in services. Public participation also has a positive effect on service efficiency and the quality of life of city residents. However, this study also found several obstacles that hinder public participation. Low awareness of the importance of the role of individuals in developing smart cities, limited accessibility, and low digital literacy are the main challenges. To increase sustainable public participation, efforts are needed that involve education, training, and strengthening of information technology infrastructure. In conclusion, public participation has a crucial role in the sustainability of Jakarta Smart City through rapid response services. Effective management of public participation can improve service efficiency, strengthen community engagement, and support sustainable urban development. Therefore, continuous efforts are needed to improve and manage public participation for long-term success. With education, training, and improved technological infrastructure, broader and more equitable participation can be realised, supporting the growth of inclusive and sustainable smart cities in the future.