There are over 12,500 diseases defined by European researchers as rare disorders occurring in less than 1:2000 live births. The majority of these manifest in childhood. The clinical picture of a rare disorder is dominated by intellectual disability of various severity and organ defects. Targeted therapy is not available for the majority of rare disorders, therefore multidisciplinary patient care is the only means of improving the quality and duration of the patient's life. In this paper, the authors share their experience organizing a system of care for patients with Cornelia de Lange Syndrome. Over the last 13 years, multidisciplinary diagnostics and consultations were provided to 92 patients and their families, including rehabilitation and psychological support. The model suggested here demonstrates a shorter diagnostic process, continuous contact with the patient, his/her family and pediatrician. Guidelines and recommendations regarding the particular rare disease should be published.