The effectiveness of percutaneous epidural stimulation has been evaluated in 11 patients with multiple sclerosis. Trial stimulation was performed at the thoracic level and lasted for 4 to 10 days. Evaluation was accomplished before the start and at regular intervals during and after the treatment. The scoring systems of the Standard Neurological Examination and of the Disability Status Scale of Kurtzke were used for evaluation of the neurological status. In addition, functionally useful changes were assessed by a physical therapist using a disability scoring technique designed at the National Multiple Sclerosis Centre at Melsbroek. Visual and somatosensory evoked potentials were also recorded at regular intervals. Six out of 11 patients claimed a subjective improvement following stimulation. But only four patients had better scoring results in the quantitative neurological testing, and for only two patients was this objective improvements functionally useful.