Autologous and non-myeloablative allogeneic stem cell transplantation are being applied worldwide in many of the transplant centers for hematological malignancies. From 2004 to 2006 we analysed the results of autologous and allogeneic peripheral blood stem cell transplantation (PBSCT) performed at Baskent University. Seven MM patients younger than 65 years old were treated with high-dose therapy with autologous PBSCT. High-dose etoposide or cyclophosphamide followed by G-CSF was used for stem cell mobilization and 3.0-11.9 (median 6.63) x 106/kg of CD34+ cells were collected. Single high dose therapy with melphalan 140 mg/m2 was performed. The incidence of grade 4 toxicity and treatment-related mortality were 0%. Complete response and tumor reduction of more than 75% were obtained in all patients. At a median followup of 10 months (range 1-29 months), all patients remained diseasefree. One patient with refractory non-Hodgkin lymphoma was treated with ifosfamide, idarubicin, and etoposide before autologous PBSCT. As analyzed by intention to treat, this patient achieved complete remission. Common side effects observed during 3 cycles of therapy were grade 3 to 4 neutropenia and thrombocytopenia. At a median follow-up of 13 months patient remained disease-free. Four patients with acute myeloblastic leukemia have been treated with non-myeloablative allogeneic peripheral stem cell transplantation. Patients received fludarabine-based preparative regimens. All patients received fully matched blood from a related donor 2 days after chemotherapy in conjuction with graft versus host disease (GVHD) prophylaxis. Chimerism analysis by cytogenetic on day 30 revealed that all patients had between 95 and 100% donor cells. Refractory patient with >90% engraftment had late autologous reconstitution by 3 months with evidence of relapse. The patient who relapsed post-transplant required allogeneic cell therapy for remission induction. All other patients in remission remained with >90% donor cell engrafment. These patients are disease-free at months 13, 10, 2. Acute GVHD grade >II occured in none of the patients.