Patients who have relapsed myeloma have failed treatment regimens and have had disease progression following their last treatment regimen. Despite newer salvage therapies, their treatment options are limited and may include best supportive care and investigational therapy. Patients with plateau-phase myeloma have a stabilized serum M-protein level without further tumor regression despite continued treatment. Recent evidence suggests that their prognosis might improve with further reduction in serum M-protein or prolongation of time to disease progression (TTP). These patients are candidates for investigational agents that could further reduce tumor burden or increase TTP.