The role of allogeneic BMT for follicular lymphoma remains to be established. From 1995 to 2000, 16 patients with follicular lymphoma underwent allogeneic BMT at our center. At the time of transplantation, two patients were in complete remission, 11 in partial remission and three had refractory disease. Fourteen patients were transplanted using a standard myeloablative conditioning regimen and two a nonmyeloablative conditioning regimen. With a median follow-up of 1184 days (range 403-1999 days) after BMT, 11 patients were alive, whereas five died of transplant-related mortality. Eight patients remained in CR 284+ to 1022+ days (median 560+ days) after BMT. Two patients relapsed 63 and 1073 days after BMT. They achieved a further complete remission after salvage treatment and remained alive 403 and 1224 days after BMT, respectively. One patient with autologous reconstitution had never been in CR after BMT. He was retreated with salvage chemotherapy but only achieved CR with subsequent rituximab treatment and was still alive, 1999 days after transplantation. The estimated 2-year overall survival and event-free survival rates were 68% and 55%, respectively. Age greater than 37 years at diagnosis, positive recipient CMV serology and ECOG performance status > or =1 at diagnosis were associated with shorter overall survival (P = 0.05, P = 0.009 and P = 0.03, respectively). Ann Arbor III-IV stage at diagnosis was associated with shorter event-free survival (P < 0.04). Allogeneic BMT seems to be effective for patients with follicular lymphoma. However, the relatively high rate of early transplant-related mortality emphasizes the need to define indications and use prospective protocols involving a less toxic transplant procedure.