The aim of this study was to examine the importance of the serum hepatitis C viral load within the first year post-liver transplant in determining posttransplant survival. A retrospective analysis of 118 consecutive hepatitis C virus-positive liver transplant recipients who received an allograft from January 1997 to September 2005 was undertaken with a median duration of follow-up of 32.4 months. Univariate and multivariate analyses were used to examine the effects of recipient, donor, surgical, and viral factors on posttransplant outcomes. A total of 620 viral load estimations were undertaken in the first 12 months following transplantation. Patient and graft survival rates at 1, 3, and 5 years were 87.8%, 79.9%, and 70.1% and 87.0%, 79.2%, and 68.2%, respectively. According to multivariate analysis, a peak viral load Ն 10 7 IU/mL (P ϭ 0.004; hazard ratio, 8.68; 95% confidence interval, 2.04-37.02) and exposure to antirejection therapy (P ϭ 0.05; hazard ratio, 2.26; 95% confidence interval, 1.01-5.38) were both independent predictors of diminished patient and graft survival and hepatitis C-related allograft failure. The only other independent predictor of hepatitis C virus-related outcome after transplant was azathioprine use, which was associated with improved outcomes (P ϭ 0.04; hazard ratio, 0.25; 95% confidence interval, 0.07-0.91). A peak viral load in the first year after transplant of Ͼ10 8 , 10 7 to 10 8 , and Ͻ10 7 IU/mL was associated with a mean survival of 11.8, 70.6, and 89.1 months respectively (P Յ 0. Cirrhosis related to chronic infection with hepatitis C virus (HCV) has emerged as the most frequent indication for orthotopic liver transplantation. Presently, approximately 50% of transplants performed in the United States and Europe are for patients infected with HCV.1 The health burden due to HCV is expected to increase to such a degree that by the year 2020, the proportion of untreated HCV patients developing cirrhosis will have increased by 30%.1 Furthermore, it is projected that the number of HCV patients with cirrhosis will double and the number of HCV patients with cirrhosis developing hepatocellular carcinoma (HCC) will increase by 80%.