Ten children who underwent allogeneic (n = 5) or autologous (n = 5) bone marrow transplantation (BMT) for chronic myelogenous leukaemia (n = 2), acute lymphoblastic leukaemia (n = 1), acute myelogenous leukaemia (n = 2), severe aplastic anaemia (n = 2), malignant histiocytosis (n = 1), neuroblastoma (n = 1) and teratoma (n = 1) were assessed for endocrinological function. Transplant preparative regimens consisted of high-dose cyclophosphamide, high-dose cyclophosphamide in combination with high-dose busulphan, high-dose melphalan as well as BACT (BCNU, cytarabine, cyclophosphamide and 6-thioguanine) chemotherapy. None of the patients received total body irradiation (TBI). Median survival following BMT was 37 months (range 7-115). Growth hormone deficiency was present in only one patient; none of the patients had abnormal thyroid or adrenocortical function. This is in contrast to previous reports in which growth hormone deficiency and abnormal thyroid and adrenocortical function occurred in a much higher percentage of patients after BMT conditioned with TBI.