A group of 16 patients with chronic-progressing type of multiple sclerosis treated by intense immunosuppression (cyclophosphamide and ACTH) were followed-up for one year after completion of therapy. The results were compared with the observation of a control group of 16 patients with a similar type of multiple sclerosis. The choice of the type of therapy was done at random, and the results were assessed by a doctor who ignored the type of therapy used. In only a part of the observed cases stabilization of the disease process was observed, in a greater number in the cases treated with cyclophosphamide and ACTH than in the those treated with ACTH alone. However, the duration of follow-up is regarded as too short for reaching final conclusions regarding the effect of therapy on the course of this type of multiple sclerosis.