Autologous non-cryopreserved bone marrow infused 8 hours after an intravenous injection of melphalan, 140 mg/m2, accelerates bone marrow recovery. This effect is most noticeable in the recovery of peripheral blood granulocytes. Twenty patients with disseminated malignant melanoma were treated with this regimen: there were 12 responses, two of them complete but the toxicity of the treatment was not sufficient to justify using this method of treatment routinely since survival was little influenced by treatment (4-11 months). In 8 patients with disseminated neuroblastoma, high dose melphalan/autograft was used in a program of combined modality treatment. Three of the patients are disease free at 16, 11 and 6 months and in one the disease is 'static', not having grown for 13 months. The treatment for this tumour deserves further exploration, and perhaps similar treatment ought to be explored for other tumours.