The European strategy for a climate-neutral economy by 2050 mandates an urgent energy transition, requiring member states to adopt sustainable, comprehensive policies. The project “Multi-sectoral Integrated Modeling platform for planning national energy transition pathways (MIMO)” addresses this need by developing an innovative suite of modeling tools—including an energy system model, a microsimulation model, a Stock Flow Consistent (SFC) model, and a SAM-based Dynamic Computable General Equilibrium (CGE) model. By integrating engineering and economic approaches, MIMO provides a cohesive framework that considers feedback effects between energy and socio-economic systems. These interconnected models assess feasible energy technology mixes, household and industrial energy demand, and both long-term structural and short-term policy impacts, offering policymakers robust support for designing effective transition strategies.