Autologous transplantation of hematopoietic stem cells has recently been proposed as a possible treatment for autoimmune diseases that are associated with a very severe prognosis. A 12-year-old girl who, since 4 years of age, had systemic sclerosis with progressive pulmonary involvement underwent autologous peripheral blood-derived stem cell transplantation (aPBSCT) using CD34+ selection, cyclophosphamide, and the infusion of the monoclonal antibody CAMPATH-1G. Following transplantation, in the absence of any treatment other than symptomatic therapy, the patient's exertional dyspnea and alveolitis disappeared and she experienced a marked improvement in skin score, height velocity, and general well-being that has persisted 2 years after the transplantation procedure. Autologous PBSCT associated with the infusion of the monoclonal antibody CAMPATH-1G appears to be a useful therapy for otherwise intractable forms of progressive systemic sclerosis.