The aim of this study was to assess the prognostic value of total serum bilirubin (TSB), gamma-glutamyl transpeptidase (GGT) and the TSB/GGT ratio in 129 consecutive cirrhotic patients, and to determine how seven other clinical and biochemical variables affect the prognostic value of these measurements. The Cox model and log rank test were used to compare survival rates at 1 year. Considered alone, encephalopathy, ascites, TSB, prothrombin time, serum albumin, GGT and the TSB/GGT ratio (TSB expressed in mumoles per liter and GGT in IU per liter were associated to the 1-year survival (p less than 0.10). The estimated per cent surviving at the end of 1 year was 20% for those with encephalopathy and 59% for those without, 46% and 62% for those with and without ascites, 28% for those with TSB greater than 3.0 mg per dl, 68% for those with TSB less than or equal to 3.0 mg per dl, 44% for those with GGT less than or equal to 100 IU per liter, 60% for those with GGT greater than 100 IU per liter, and 12% for those with TSB/GGT greater than 1, 66% for those with TSB/GGT less than or equal to 1. With the Cox model, which was used to assess the combined effect of several prognostic variables, GGT was the only biochemical variable which added significant prognostic value to TSB. The combination of TSB and GGT added significant prognostic value to encephalopathy and ascites.