Almost every day brings new reports of a “rare” (“orphan”) disease – a disease that requires multidisciplinary knowledge and particular caution in making diagnostic and therapeutic decisions.The Classification of Rare Cardiovascular Diseases (RCD) is aimed at (1)facilitating recognition of RCDs, and (2) grouping the expertise in the main fields of RCDs.The classification provides a systemic framework for clinical examples selected from a broad group of patients who have been consulted in the CRCD on a regular basis by national and international experts during live videoconferences.