A 7 year old Kurdish girl presented with a cerebral infarction and a resulting hemiparesis following a blood transfusion. Examination of the blood film suggested sickle cell anaemia. However a simultaneously carried out haemoglobin electrophoresis showed haemoglobin S and haemoglobin D. The diagnosis of haemoglobin SD disease was thereby established. This kind of haemoglobin disorder usually shows a mild clinical manifestation. According to our knowledge such serious cases have not been published before. With this disease the main emphasis is on the prevention of recurrent cerebral infarctions bay a long-term transfusion programme whereas the effects of the cerebral infarction are treated in the usual way.