Much progress has been made in the treatment of patients with multiple myeloma (MM). The introduction of new drugs such as thalidomide, bortezomib and lenalidomide has created more possibilities for patients than many years before. In addition, autologous peripheral blood stem cell transplantation after high-dose melphalan has become the standard of care for younger patients. Allogeneic stem cell transplantation is an experimental option for those younger patients with a human leucocyte antigen identical donor. Because of these rapid developments and many treatment options we need good quality clinical studies that can guide us in what to do in everyday practice. This review will focus on those studies that have changed the treatment guidelines for patients with MM.