THE PATHOPHYSIOLOGY of most autoimmune diseases is often poorly understood. EXPERIMENTAL CONSIDERATIONS and clinical experience suggest that high doses immunoablation followed by stem cell transplantation is a therapeutic option to consider for certain severe autoimmune disorders. THE CONCEPT OF RESTORING NORMAL IMMUNE REACTIVITY must in part br true since current results of 466 transplants (445 autologous, 21 allogeneic) patients suffering from various autoimmune diseases show a beneficial outcome in approximately 2/3 of the patients. TO IMPROVE THE EFFICACY AND SAFETY OF SUCH AN AGGRESSIVE PROCEDURE in patients with potentially affected vital organs by the underlying autoimmune disease, it is especially important to follow international consensus guidelines and to centrally collect clinical data for in depth analysis in the EBMT International Stem Cell Project for Autoimmune Disease in Basel, Switzerland. PHASE III STUDIES ARE RUNNING FOR SYSTEMIC SCLEROSIS (Astis, Autologous Stem cell Transplantation International Rheumatoid Arthritis Trial) started in 2003. A STUDY PROJECT IS PLANNED FOR MULTIPLE SCLEROSIS (Astims, Autologous Stem cell Transplantation International Multiple Sclerosis).