In the period 1971-1990 91 children underwent splenectomies in the University Hospital of Nijmegen. The most important indications are hereditary spherocytosis, Hodgkin's disease and very severe immune thrombocytopenic purpura (ITP). Splenectomy after a traumatic rupture of the spleen has become less frequent: from 20% in 1971-1980 to 4% in 1981-1990. Short-term complications included thrombocytosis (84%), fever without an obvious cause (46%), which is quite regularly seen in patients suffering from Hodgkin's disease (48%), and infections of the respiratory tract in 10% of the patients. The platelet count shows a steady increase in the first nine post-operative days. No thromboembolic complications were seen. Based upon the literature there seems to be no reason at this moment for anti-platelet aggregation therapy when platelet counts are below 1000 x 10(9)/l. More information about long-term complications was obtained through a questionnaire completed by general practitioners. The morbidity through overwhelming post splenectomy infection (OPSI) is 3.8% (3/79), the mortality of OPSI is 2.5% (2/79). Underlying diseases, especially those which involve the immunological system as auto immune haemolytic anemia (AIHA), seem to play an important role in the possible development of OPSI (morbidity 2/11, 18%).