There were 70 admissions from a regional paediatric oncology centre to the intensive care unit over a six and a half year period. Patients were divided into those with systemic infections (n = 19), respiratory infections (n = 15), metabolic effects (n = 9), tumour mass effects (n = 10), neurological complications (n = 8), and others (n = 9). The overall survival was 51%. Patients admitted with metabolic or tumour mass related effects had the best prognosis with a survival of 84%. If dialysis is required in this group of patients then continuous arteriovenous haemofiltration is recommended. Patients with systemic or respiratory infections comprised the main poor prognosis group with a survival of 26%. For patients with a systemic infection who required ventilation, the mortality was 100%. The outlook for patients with a generalised encephalopathy was also poor, with no neurologically intact survivors. The median APACHE-II (acute physiology and chronic health evaluation) score for patients who died was 27 and for survivors was 16. There is a need for close cooperation between staff of intensive care and paediatric oncology units. Alternative treatments should be considered for patients with systemic infections who require ventilation.