Many Japanese regional cities face population decline, industrial constraints, and limited resources for decarbonization, yet hold untapped potential in the residential and commercial sectors through local energy use. This chapter develops a carbon neutrality (CN) strategy for Tochigi Prefecture and evaluates its feasibility with particular attention to social acceptance. Six scenarios were created, combining existing measures such as energy-efficient appliances, building insulation upgrades, and renewable heat utilization, ranging from nationally aligned policies to more ambitious, locally tailored options. Each scenario was assessed for CO₂ reduction, economic ripple effects, and job creation, and tested through participatory deliberation in a Multicultural Public Sphere Forum. Enhanced scenarios achieved 54–64% CO₂ reductions by 2030 compared with 2013 levels, with insulation-related measures receiving over 70% support. The analysis suggests that social acceptability increases when multiple co-benefits—environmental, economic, health, and comfort—are achieved simultaneously. Furthermore, the quantitative evidence that carbon neutrality can be attained through the deployment of readily available technologies highlights its potential to shift from an abstract policy goal to a concrete, feasible initiative embedded in daily life, thereby redefining how it is perceived and prioritized within local communities.