Transplantation remains the only cure currently available for patients with thalassemia. Results of transplantation in this disease have steadily improved over the last two decades due to improvements in preventive strategies, effective control of transplant-related complications and development of new preparative regimens. High-resolution HLA typing has enabled physicians to perform transplants from unrelated volunteer donors for thalassemia with results comparable to those obtained employing an HLA-identical sibling. The probabilities for obtaining thalassemia-free survival after transplantation from an HLA-identical donor, family member or matched unrelated donor are between 85 and 87%. Therefore, when an HLA-identical donor is present, the transplantation of allogeneic stem cells should be performed as allogeneic gene therapy.