The Community-Based Integrated Care System (CICS) in Japan integrates five key domains—housing, healthcare, long-term care, livelihood support, and prevention—to support elderly’ independent living. However, rising demand for social welfare services and financial constraints challenge its sustainability. Policymaking within CICS requires cross-sectoral coordination, yet traditional approaches often fail to capture interdependencies and long-term impacts. This study develops a gaming simulation to facilitate policy discussions within CICS, enabling stakeholders to experience decision-making processes and assess the effects of policy choices on service sustainability. Players act as municipal policymakers, allocating budgets across CICS domains and evaluating long-term policy outcomes through a CICS simulator using an agent-based modeling framework. The game is structured on Lasswell’s context-oriented approach, organizing stakeholder perspectives, regulatory mechanisms, and decision-making processes. The simulation evaluates policy sustainability based on short-term indicators, such as service utilization rates and demographic shifts, and long-term indicators, including healthy life expectancy and financial sustainability. By visualizing trade-offs and sectoral interactions, the game serves as a scenario-based learning tool, enhancing stakeholder understanding of policy interdependencies. This research contributes to policymaking by providing an inter-active framework for optimizing care service delivery and fostering co-creation in municipal governance.