Studies were made on 59 children (cardiac 42, orthopaedic 13, miscellaneous 4) scheduled for autologous blood donation before elective surgery. The donor-patients' ages ranged from 3 to 15 years (mean 9.9 years) and their weights from 13 to 70 kg (mean 34 kg). All patients received 50-100 mg of oral iron sulphate per day. As a rule, about 10% of intravascular blood volume was drawn once a week. Before surgery, an average of 720 ml of autologous blood per patient was prepared. Two patients failed to donate autologous blood because of anxiety about the procedure; however, none of the donors was deferred due anaemia associated with the phlebotomy. Of the 53 patients undergoing surgery and participating in autologous predonation, 50 (94%) were able to avoid homologous blood transfusion. 600 ml of homologous blood were transfused to each of 2 orthopaedic patients and 400 ml to 1 cardiac patient. We conclude that a predeposit autologous transfusion programme is logistically possible in small children when the patients are cooperative.