Collecting the data and information which are perfectly described by the Spanish Society of Internal Medicine: “more tan 6000 nosological entities belong to the so called group of rare diseases. Despite the great diversity, they share common characteristics: they have a prevalence of less than 5 cases/100.000 inhabitants, they have a genetic origin in more than 80% of all cases, they are serious and degenerative, and in many cases, they limit the life quality of patients due to the loss of autonomy. The lack of medical-scientific knowledge about these diseases causes a significant delay in their diagnosis and their treatment approach and it requires an interdisciplinary and integral attention and care. In this sense, the role of the internist is extremely important”(original text, collected from fesemi.org).