WE REPORT A prospective, randomized, blinded clinical trial comparing seizure and neuropsychological outcomes from anterior temporal lobectomies between two groups of patients. One group (n = 34) underwent hippocampal resection posteriorly to the anterior edge of the cerebral peduncle (partial hippocampectomy). In the other group (n = 36), the hippocampus was removed further to the level of the superior colliculus (total hippocampectomy). The amount of lateral cortical resection was the same between groups. Patients were and neuropsychological morbidity. At 1 year postoperatively, the total hippocampectomy group had a statistically superior seizure outcome compared with the partial hippocampectomy group (69 versus 38% seizure-free), and examination of time to first seizure (survival analysis) revealed significantly superior outcomes associated with total hippocampectomy. There was no increased neuropsychological morbidity associated with the more extensive hippocampal resection.