Individuals whose conditions have eluded medical diagnoses may apply to become UDP participants and, if invited, are admitted to the NIH Clinical Center in Bethesda, Md. Each patient undergoes a week of diagnostic tests and expert consultations provided for free at one of the world's largest medical research institutes. The patient is examined by a multidisciplinary medical team with a deep base of knowledge about rare and common diseases. The team, drawn from various NIH institutes and centers, studies a patient's clinical and laboratory results for diagnostic clues while the patient is in the Clinical Center and in the weeks and months following their visit