The causes of death in 21 adults and 23 children in a consecutive series of 180 liver transplantations were reviewed and classified into four categories. A previously described preoperative risk score was applied prospectively to estimate the relative risk of mortality following liver transplantation in adults. Categorization of the causes of death allowed for a systematic search for errors in management and technique. Comparison of the preoperative risk score with the cause of death category revealed that higher-risk adults were most likely to die of causes related to preoperative morbidity. They also accrued higher hospital costs, regardless of outcome. The data are useful for designing strategies to reduce mortality. However, the inexorable role that preoperative morbidity has on outcome was also emphasized. This has important implications in developing strategies to reduce the costs of liver transplantation and to provide optimal distribution of scarce donor organs.