Background: Extracorporeal photopheresis is an immunomodulatory technique in which a patient's leukocytes are exposed to ultraviolet-A light after pretreatment with 8-methoxypsoralen (methoxsalen). There have been few reports describing the use of extracorporeal photopheresis in lung transplant recipients. Methods: We reviewed our experience using extracorporeal photopheresis in 8 lung transplant recipients since 1992. All 8 patients had progressively decreasing graft function and 7 were in bronchiolitis obliterans syndrome grade 3 before the initiation of photopheresis. One patient had undergone a second transplant operation for obliterative bronchiolitis. Two patients had a pretransplantation diagnosis of chronic obstructive pulmonary disease, 1 α1-antitrypsin deficiency, 1 cystic fibrosis, 1 bronchiectasis, 1 idiopathic pulmonary fibrosis, and 2 primary pulmonary hypertension. Before refractory rejection developed, all patients had been treated with 3-drug immunosuppression and anti-T-cell therapy. The median time from transplantation to the start of extracorporeal photopheresis was 16.5 months and the median number of treatments was 6. Results: The condition of 5 of 8 patients subjectively improved after extracorporeal photopheresis therapy. In these 5 patients photopheresis was associated with stabilization of the forced expiratory volume in 1 second. In 2 patients there was histologic reversal of rejection after photopheresis. With a median follow-up of 36 months, 7 patients are alive and well. Three patients required retransplantation at a median of 21 months after completion of the treatments. Four patients have remained in stable condition after photopheresis. There were no complications related to extracorporeal photopheresis. Conclusion: We believe that this treatment is a safe option for patients with refractory lung allograft rejection when increased immunosuppression is contraindicated or ineffective.