Intensive chemotherapy and high dose chemotherapy with bone marrow transplantation are 2 complementary therapeutic procedures for non Hodgkin's lymphomas. In children, indications for BMT in NHL are limited to patients who fail to achieve complete remission and for patients in sensitive relapse. In adults, the role of BMT is also recognized for patients who fail to achieve remission with initial therapy. The advantage of either conventional regimens or massive therapy with BMT for patients with poor prognostic criteria is still under evaluation (LNH 87 protocol). The PARMA protocol tests, in a multicenter randomized study, the value of BMT for patients in sensitive relapse. Results of BMT for patients with refractory NHL and resistant relapse, remain poor. The role of BMT in low grade lymphomas is debatable. The trials for evaluation of massive chemotherapy and BMT in NHL will contribute to defining the potential role of this therapy in France: a potential 1,000 cases per year may be treated by this method.