Hallermann–Streiff Syndrome or oculo-mandibulo-dyscephaly syndrome is a rare genetic disorder that is primarily characterized by head, face and dental abnormalities, with a penetrance of 50-80 %. A young female patient presented herself in the Prosthodontic Department of the Dental Faculty, University of Szeged for treatment. Her primary care dentist considered the case to be too complicated. The patient’s principal symptoms were: microcephalia, hypodontia, hypoplasia mandibulae and bird face. The patient was not satisfied with the shape and esthetic of her teeth. In order to improve function and esthetics of the chewing apparatus and general appearance, a fixed upper bridge was prepared. The treatment of patients with Hallermann–Streiff Syndrome may be complicated, but careful planning and adequate bridge construction may fulfil the patient’s requirements. General dentists may also achieve the same result, instead of referring such patients to specialists.