Integrated energy planning is intended as a set of approaches, processes and practices aimed at bringing together different disciplinary contributions dealing with manifold energy issues.The aim of this Issue is to debate on tools and methods addressingthe energy transition in the Mediterranean countries, moving fromthe experience of two Erasmus + projects, E-Resplan and Eneplan, in which Roma Tre University has been respectively partner and coordinator.In the light of national and international research programs wellrooted within legislative and regulatory frameworks, the papersconjure up an original palette of issues bridging energy transitionapproaches led by energy efficiency targets, notably building stockretrofitting, and by the urge for decarbonization and energy security requirements, with environmental concerns about climatechange, biodiversity and the ecological approach.