The incidence of early infectious complications after splenectomy was retrospectively studied in 133 patients operated on between 1975 and 1982. Comparisons were made with a control group. Among the patients in whom splenectomy was performed because of trauma, iatrogenic injury during surgery for benign disorders, as a staging operation in malignant lymphoma or for haematologic reasons, the rate of early postoperative infection ranged from 14 to 29%. In the controls, who underwent selective proximal vagotomy in the same period, the post-operative infection rate was 5%. Of the 133 patients in the splenectomy group, 17 were subsequently hospitalized for infectious disorders (18 months-8 years postoperatively). Because of the high incidence of postoperative infections, prophylactic antibiotic treatment in connection with splenectomy is recommended.