Known prognostic factors in neuroblastoma were analyzed in 124 children to determine which were independent and which were most useful in predicting outcome. The following factors were analyzed: age, sex, stage of disease, serum neuron-specific enolase (NSE), serum ferritin, E-rosette inhibition, urinary catecholamines, and histologic type according to the criteria of Shimada. Estimates of survival were calculated using the method of Kaplan and Meier. The overall survival for 124 patients was 60% at 2 years. There were significant differences in survival by pathology, age, NSE, ferritin, vanilmandelic acid (VMA): homovanillic acid (HVA) ratio, and stage. There was a strong association among NSE, age, stage, and ferritin. Using the recursive partitioning approach, it was possible to subdivide patients into three groups (based on diagnostic values of ferritin, age, and stage) with a good, intermediate, and poor prognosis and estimated 2-year survival of 100%, 62%, and 19%, respectively. Further analysis could not be done because of small numbers in the subgroups, but the results suggest that combinations of age, stage, serum ferritin, and histologic type may be able to define two populations: favorable with 80% + 2-year survival and unfavorable with less than 20%.