Sickle cell disease is a hereditary chronic hemolytic anaemia mostly found in negroes. The blood of these patients contains hemoglobin S. Absence of oxygen determines the sickling to the red blood cells. In the heterozygous state clinical manifestations usually are absent. The homozygous form shows different symptoms. The progressive course with hemolytic, aplastic or thrombotic crises mostly ends in an early death in infancy or childhood. Treatment is largely palliative. Transfusions, treatment of the crises and general measures play the most essential role.