Prader-Willi syndrome (PWS) is a rare and complex genetic disease, with numerous implications on metabolic, endocrine, neuropsychomotor systems, and with behavioral and intellectual disorders. Rare disease patient registries are important scientific tools to collect clinical and epidemiologic data, to assess the clinical management including the diagnostic delay, to improve patients’ care and to foster research to identify new therapeutic solutions. The European Union has recommends the implementation and use of registries and databases. The main aims of this paper are to describe the process of setting up the Italian PWS register, and to illustrate our preliminary results. The Italian PWS registry was established in 2019 with the aims to describe the natural history of the disease, to determine clinical effectiveness of health care services, to measure and monitor quality of care of patients. Information from six different variables are included and collected into this registry: demographics, diagnosis and genetics, patient status, therapy, quality of life and mortality. The analyses of these six variables allowed to highlight important clinical aspects and natural history of PWS useful to inform future actions to be taken by national health care services and health professionals. Read the full article here.