In a retrospective study we investigated the clinical course of patients who required intensive care support after bone marrow transplantation. Out of 25 patients only 5 (20%) survived treatment in the intensive care unit (ICU) and this group showed a significantly lower age, lower APACHE III and organ-failure scores and higher serum albumin values, as well as a longer interval between bone marrow transplantation and admission to intensive care. However, no patient requiring mechanical ventilation primarily for pneumonia or other infections arising as a complication of bone marrow transplantation survived intensive care. All patients requiring ventilation for more than 24 hours died in hospital. Of the 5 patients surviving ICU treatment only 3 were eventually discharged from hospital and only one single patient was alive after 6 months. Hence, current intensive care management appears to be indicated in only a small group of patients after bone marrow transplantation.