The International Meeting on Pulmonary Rare Diseases and Orphan Drugs is the only European event dedicated to different types of rare pulmonary diseases affecting both parenchymal and vascular structures. Inter-specialization and transversality are the fundamental frameworks in which this meeting has been designed, by ranging from vasculitis, to pulmonary fibrosis, diseases of connective tissue, and pulmonary hypertension. If we can open up new prospects and opportunities for rare diseases, by wandering between medical specializations and involving different medical specialists, we may explore some common pathogenic mechanisms in the development of rare diseases; moreover, by integrating different sources of scientific knowledge, we may also test innovative therapeutic approaches.