OBJECTIVES: There is no integrated approach to the problem of orphan diseases (OD) in Ukraine. Diagnosis of these illnesses is often complicated and delayed, the treatment is often ineffective because of the lack and unavailability of essential medicines and methods of treatment, the quality of life for most patients remains poor. The Law of Ukraine ‛On amendments to the Basic Laws of Ukraine on Health Care on prevention and treatment of rare (orphan) diseases’ has been recently issued. It governs the measures of OD prophylaxis. METHODS: According to the Law, in order to improve OD patient care, a work on medical and technological documents on such topics as mucopolysaccharidosis, Gaucher disease, phenylketonuria, hemophilia was launched. The development of medico-technological documents was done in a few steps. Firstly, the search for clinical guidelines was conducted in the GIN library and other sources. Secondly, the primary selection and appraisal with  AGREE II instrument have been carried out. The next step was adaptation of clinical guidelines and development of clinical protocols of the medical care. It was conducted by multidisciplinary working groups including leading specialists in clinical genetics, health care managers and patients organizations. RESULTS: Today the clinical protocols of treatment of mucopolysaccharidosis patients, based on evidence of the effectiveness of medical technologies, pharmacotherapy and organizational principles of its provision, were approved. The documents contained modern approaches for diagnostics and treatment of mucopolysaccharidosis, which are ajusted to the health care system of Ukraine. CONCLUSIONS: Harmonization of treatment practices of OD in Ukraine with international best practice will bring the treatment of these states in Ukraine to a new level and provide thorough measures aimed at the development of screening and prevention programs, diagnostics and treatment, as well network collaboration among health services, educational institutions, public etc.