Over a six-year period, 130 patients with medically intractable epilepsy were assessed for possible surgical treatment. Initial assessment comprised full neurological and neuropsychological examination, computed tomographic and magnetic resonance imaging brain scanning, and simultaneous video and surface plus sphenoidal electroencephalographic (EEG) recordings of typical seizures. Forty-one patients (32%) underwent further video and EEG recordings of their seizures with depth (intracerebral) or strip (subdural) electrodes. After these assessments 46 patients (35%) underwent surgery, and follow-up for six months to six years is reported in 41 patients. Of 30 patients who underwent temporal lobe surgery, 21 (70%) are free of seizures and four have had significant seizure reduction, meaning that 83% benefited from surgery. Optimal results were obtained for complex partial seizures when depth electrode recordings were obtained and when abnormal tissue was removed. Six extratemporal resections abolished seizures in two patients, and four others showed worthwhile improvement. Five patients underwent corpus callosotomy, resulting in a worthwhile improvement in three and modest improvement in two patients. No deaths or major complications occurred. It is concluded that surgical intervention can be beneficial for up to 30% of patients with medically intractable epilepsy, and referral of these patients to an appropriate institution is encouraged.