In this study, multimodal event related potentials (ERP) were recorded from 52 epileptic patients to determine a possible relationship between ERP components and certain characteristics of this population, i.e., seizuretype, EEG findings; duration of the disease and type of anticonvulsant treatment. Electrophysiological findings were compared with those obtained in nineteen normal subjects, age matched with the patients group. Epileptic patients had significant abnormalities in all ERP modilities. Mean N2 and P3 latencies were significantly prolonged and mean latency of motor related cortical potential (MRCP) were significantly shorteened in all seizure type and duration of disease. The most significant effect was shown on CNV components and amplitude of MRCP in those receiving more than one anticonvulsant. Patients on anticonvulsant monotherapy and polytherapy had longer P3 latency. Shortening of latency in MRCP was shown both in those receiving and not receiving medication. Patients with paroxysmal electroencephalographic discharges had shortening of latency in MRCP and in those with local electroencephalographic discharges had prolongation of latencies in N2 and P3. The results suggest that different ERP components are affected by dillerent variables, i.e., seizure type, EEG findings, duration of the disease and type of anticonvulsant therapy.