Recent reports have suggested that patient-controlled analgesia is an effective means of narcotic administration in postoperative patients. This prospective investigation was undertaken to determine the efficacy and safety of patientcontrolled anesthesia infusion after cesarean section. During a recent ten-month period, 130 patients were assigned randomly to receive meperidine by pump or intramuscular injection. Meperidine consumption using the device varied widely to meet individual needs. Overdosage and drug dependence were not encountered with the prescribed drug concentrations. The patient-controlled analgesia method provided less sedation and more immediate pain relief without the need for painful injections. The additional cost of renting the infuser device was offset by combined patient and nursing satisfaction. We conclude that patientcontrolled infusion of meperidine is safe and effective in satisfying individual patient needs after cesarean section.