Treatment of aplastic anaemia in 28 patients with oral methenolone 1–2 mg/kg for from 2 to 12 months resulted in normalisation of the blood count in 12 cases (43%). The remission rate was 60% for patients with a treatment period of at least 3 months. Cholestatic jaundice occurred in 2 cases (7%) but these recovered after discontinuing the drug. Other side effects were not severe enough to cause interruption of the treatment. There seems to be no doubt that methenolone by mouth is a useful treatment of patients with aplastic anaemia. The trial of therapy should be extended to at least 6 month