Between 1976 and 1988, 7 patients with systemic lupus erythematosus (SLE) underwent splenectomy for severe peripheral thrombocytopenia (platelet count below 30,000/mm3) which had resisted corticosteroid therapy (n = 7), high-dose immunoglobulins (n = 4), vincristine (n = 2), danazol (n = 1), cyclophosphamide and plasma exchanges (n = 1). No infective or non-infective complication of splenectomy was observed. One patient died of intracerebral haemorrhage 3 years later, after several recurrences of thrombocytopenia. The 6 survivors have normal platelet counts (more than 150,000/mm3) after splenectomy, over a mean follow-up period of 80 months. Two of these 6 patients never had recurrent thrombocytopenia and have not received any treatment for 17 to 102 months. Four patients are still under prednisone in doses lower than 30 mg/day. Among these, 2 had recurrent thrombocytopenia 2 and 60 months respectively after splenectomy and responded favourably to another course of corticosteroids associated, in one case, with cyclophosphamide. Thus, splenectomy is an effective treatment of the thrombocytopenia associated with SLE. However, the possibility of early or late recurrences makes it necessary to reserve splenectomy to those cases where medical treatment has failed or is contra-indicated.