Five patients with resistant non-Hodgkin lymphoma (NHL) were given granulocyte-macrophage colony-stimulating factor (GM-CSF, 250 micrograms/m2 daily) after the BEAM pretransplant chemotherapy regimen (carmustine 300 mg/m2, etoposide 1.2 g/m2, cytarabine 800 mg/m2, melphalan 140 mg/m2) because persistent lymphoma cell infiltration of the bone marrow precluded autologous bone-marrow transplantation (BMT). In three patients full haemopoietic reconstitution occurred, with similar kinetics to that seen after autologous BMT. The other two patients died without sustained haemopoietic recovery. GM-CSF may replace autologous BMT in highly selected cases of NHL with progressive disease and bone-marrow involvement.