Fondazione Telethon is one of the main Italian biomedical charities, founded in 1990 on the initiative of a group of patients suffering from muscular dystrophy. Its mission is to achieve the cure of rare genetic diseases through scientific research of excellence, selected according to the best practices shared internationally. Through a unique method in the Italian panorama, it follows the entire “research chain” dealing with fundraising, selection and funding of projects and the research activity itself carried out in the centers and laboratories of the Foundation. Telethon also develops collaborations with public health institutions and pharmaceutical industries to translate the results of research into therapies accessible to patients. Since its foundation, Telethon has invested 623,69 million euros in research, has funded 2,804 projects with 1,676 researchers involved and 589 diseases studied. To date, thanks to Fondazione Telethon, the first gene therapy with stem cells in the world has been made available, thanks to the collaboration with the pharmaceutical industry. Strimvelis, this is the commercial name of the therapy, is intended for the treatment of ADA-SCID, a severe immunodeficiency that compromises the body’s defenses from birth. Another gene therapy resulting from Telethon research made available is the one for a serious neurodegenerative disease, metachromatic leukodystrophy, with the commercial name of Libmeldy. This therapeutic approach is in an advanced stage of clinical trials for another immunodeficiency, Wiskott-Aldrich syndrome. Other diseases on which the gene therapy developed by Telethon researchers has been evaluated in patients are beta thalassemia and two metabolic diseases of childhood, mucopolysaccharidosis type 6 and type 1. In addition, within the Telethon institutes a targeted therapeutic strategy is being studied or developed for other genetic diseases, such as hemophilia or various hereditary vision defects. In parallel, the study of basic mechanisms and potential therapeutic approaches for diseases still unanswered continues in all laboratories funded by Telethon.