We describe our experience with the use of a single non-myeloablative preparative regimen in stem-cell transplantation (NST) in 37 heavily pretreated patients > or =55 years. The conditioning regimen consisted of fludarabine, low-dose busulfan, and antithymocyte globulin. Acute graft-versus-host disease (GVHD) grade III-IV and chronic GVHD developed in 15.6% and 44.4% of cases, respectively. With a median follow-up period of 22 (range 3-113) months, the 1-year overall survival and disease-free-survival were 55% and 53%, respectively, while the overall non-relapse mortality was 35%. In conclusion, reduced intensity stem cell transplantation is feasible and effective in patients > or =55 years. Age per se, should no longer be considered as a contra-indication to stem cell transplantation.