Clinical data and the prognosis are presented for an epidemiological group of multiple sclerosis (MS) patients. Symptoms and signs of MS, with the exception of optic nerve involvement, were less frequent in the group of 221 patients from the epidemiological area of Southern Lower Saxony than in the hospital series (n = 1837), although the mean duration of the disease was somewhat longer in the epidemiological group. Fifty-two percent of the latter were unrestricted or minimally restricted upon examination compared to 26% of the hospital group. Taking a progression index as a measure for prognosis (disability grade divided by the duration of the disease) 36% of the epidemiological group belonged to a benign category compared to 16% in the hospital group. The progress of these patients was not more than 1 grade of disability within a 5-year-period (progression index 0.2 or less). A malignant course was defined as a progression of at least 7 grades during a 5-year period (progression index 1.4 or more). Ten percent of the hospital series belonged to this category compared to 2% of the epidemiological group. Thus data from a representative group of patients show that the overall prognosis of MS is considerably better than generally suspected.