The utility of the WMS–III in detecting lateralized impairment was examined in a large sample of patients with temporal lobe epilepsy. Methods of analysis included evaluation of group means on the various indexes and subtest scores, the use of ROC curves, and an examination of Auditory–Visual Index discrepancy scores. In addition, performance on immediate and delayed indexes in the auditory and the visual modality was compared within each group. Of the WMS–III scores, the Auditory–Visual Delayed Index difference score appeared most sensitive to side of temporal dysfunction, although patient classification rates were not within an acceptable range to have clinical utility. The ability to predict laterality based on statistically significant index score differences was particularly weak for those with left temporal dysfunction. The use of unusually large discrepancies led to improved prediction, however, the rarity of such scores in this population limits their usefulness. Although the utility of the WMS–III in detecting laterality may be limited in preoperative cases, the WMS–III may still hold considerable promise as a measure of memory in documenting baseline performance and in detecting those that may be at risk following surgery. (JINS, 2001, 7, 881–891.)