The usefulness of multimodal evoked potentials for the diagnosis of Multiple Sclerosis (MS) is established. Our purpose was to try to set of 3 EPs (BAEP, median SEP and trigeminal SEP) in the evaluation of brainstem dysfunction. 53 definite and probable MS patients have been examined; they were allotted to 3 groups according to the duration of the disease. Our results showed that median SEP is the most sensitive investigation, while BAEP and trigeminal SEP were abnormal in a smaller number of cases. The combined use of median and trigeminal SEPs supplied sufficient information on brainstem function, without using the complete set of EPs. No significant relation between EP abnormalities and duration of the disease was found.