Connective tissue dysplasia (hereditary collagenopathy) presents a group of genetically heterogenous and clinically polymorphic pathological conditions, associated with disturbances in the forming of connective tissue during the embryonal and postnatal periods. Differentiated dysplasias include monofactor diseases with an established genetic defect and clear clinical symptoms, such as Marfan's syndrome, Ehlers-Danlo's syndrome, and osteogenesis imperfecta. The variants of non-differentiated hereditary dysplasias include primary mitral valve prolapse and other minor heart anomalies, tracheobronchial dyskinesia, visceroptosis, join hypermobility, congenital chest deformations, "weakness" of the ligamentous apparatus of the foot and the spine, and a range of other prevalent pathological changes. The author adduces his own observation of a patient with Marfan's syndrome.