Sickle cell disease (SCD) is encountered in all parts of the world where plasmodium falciparum has been endemic and has spread by migration to the temperate countries of the world resulting in a heavy caseload in Northern Europe and the United States. These patients in the temperate climates manifest most of the clinical problems associated with SCD in Tropical Africa and the West Indies. There are, however, differences between the groups in both the frequency and presentations of the clinical syndromes. The clinical management of SCD is discussed with particular reference to the potentially fatal sequestration syndromes: splenic, hepatic, 'the girdle syndrome' and 'the chest syndrome'. In all clinical situations encountered in SCD blood transfusions should be by isovolaemic exchange unless there is a marked fall in haematocrit (less than 5 g/dl) as may occur with sequestration and aplasia. The criteria for exchange transfusion in the chest syndrome are a pAO2 of less than 60 mm Hg while breathing air or a rapidly deteriorating clinical picture. Analgesia for vaso-occlusive sickle pain should be adequate and freely available which often requires the parental administration of opiates. We have delineated a small sub-group (6%) of SCD patients, 'the non-copers', who manifest a high demand for analgesia. The prospects for cure, and the techniques and issues for antenatal diagnosis are reviewed demonstrating the importance of education and counselling. The significant reduction in mortality and morbidity of children with SCD taking penicillin prophylaxis is emphasised with the need for its early institution.