The CHOP regimen (cyclophosphamide vincristine, adriamycin, prednisone) is considered since twenty years as the standard treatment of disseminated aggressive non-Hodgkin's lymphomas and cures approximately 30% of patients. More recently, intensive chemo(radio)therapy followed by rescue with bone marrow or blood hematopoietic stem cells has become the standard treatment of chemosensitive relapses of aggressive non-Hodgkin's lymphomas. Consequently, two questions with practical applications have arisen and are discussed in this review: Is it justified to increase the dose intensity of chemotherapy, using either single treatment intensification with stem-cell rescue, or sequential intensified chemotherapies, especially in cases with adverse prognostic factors? On the contrary, is a decrease in treatment intensity compared to CHOP chemotherapy, especially in elderly patients, harmful to the patient?