The Energy Efficiency Directive poses major challenges for municipalities with more than 45,000 inhabitants in defining local heating and cooling plans, especially in Southern Europe, where needs differ from those in central and northern regions. Many cities rely on decentralised, ageing systems, inefficient building stock, outdated equipment, and slow uptake of more efficient technologies. Plan4COLD addresses this by promoting an integrated approach combining urban planning, building renovation, and stakeholder and citizen engagement to support efficient, renewable-based heating and cooling solutions. Its methodology helps build capacity among public and private actors, supports plan development in several Southern European cities, and will inform policy recommendations while encouraging wider uptake.