Inclusion Criteria:  Minor and adult patients with rare diseases aged of at least 6 years old and followed at the Necker Enfant Malades Hospital, Paris Patients with the 3 most frequent rare diseases of each rare disease Necker reference center participating in the study (10 centers : Chronic And Malformative Disorders Of The Esophagus / Inflammatory diseases of the bile ducts and autoimmune hepatitis / Constitutional Bone Diseases / Inherited Metabolic Diseases / Biliary Atresia And Genetic Cholestases / Vascular Diseases Of The Liver / Developmental Anomalies and Malformative Syndromes of Ile-De-France / Rare Causes Intellectual Disabilities / Complex congenital heart defects / Childhood cerebrovascular pathologies) Patients who consulted between 1.1.2017 and 1.1.2020 the relevant rare disease reference center at Necker hospital Patients seen at least once in the medical genetics department of Necker Hospital Information and non-opposition of adult patients / holders of parental authority of minor patients and minor patients to participate in the study  Exclusion Criteria:  Patients who do not speak French