Nontumoral epileptogenic lesions account for the major pathological group of surgical specimens obtained from patients with temporal or extratemporal drug-resistant epilepsy. Hippocampal sclerosis remains the predominant etiology, but cerebral cortical dysplasias actually make up the second major cause of nontumoral epilepsy and are increasingly recognized. The percentage of vascular lesions or glial/glio-mesodermal scars remains stable, but the minor or nonspecific lesion group is decreasing because of imaging investigation technique improvement.