The study is designed as a Phase III, multi-center trial of tandem autologous transplants versus the strategy of autologous followed by Human Leukocyte Antigen (HLA)-matched sibling non-myeloablative allogeneic transplant. Study subjects will be biologically assigned to the appropriate arm depending on the availability of an HLA-matched sibling. There is a nested randomized phase III trial of observation versus maintenance therapy following the second autologous transplant for patients on the tandem autologous transplant arm.