Recurrences of CNS infarction often lead to progressive neurologic disability in sickle cell anemia. To prevent such reccurrence, a periodic blood transfusion program was begun in 1969. Currently, 27 patients are on this regimen. Before inclusion in the program, 12 patients had had one to nine CNS recurrences each. Since the program was started, two patients have had transient CNS ischemia. There were no other recurrences and none of the patients have shown progression of neurologic abnormalities. In addition, there was a striking decrease in bacterial infection and pain. We conclude that periodic transfusions are effective in preventing recurrent CNS infarction in sickle cell anemia. The benefits must be weighed against the potentially serious problem of iron overload, as evidenced by moderately elevated serum ferritin values.