Recurrence of viral infection and hepatitis is a common problem for patients undergoing LT for hepatitis B or hepatitis C. In patients with hepatitis B who do not receive immunoprophylaxis, recurrence of HBsAg positivity is virtually universal and is usually associated with rapidly progressive hepatitis that jeopardizes long-term patient and allograft survival. HCV infection recurs in 80% to 100% of patients, but only 50% develop histologic features of hepatitis, which are generally mild and do not significantly decrease life survival. Long-term HBIg prophylaxis is currently the only effective strategy to prevent or modify HBV recurrence. At present, there is no effective prophylaxis for recurrence of HCV infection. Preliminary results suggest that interferon therapy may benefit a minority of patients with either recurrent HBV or HCV infection after LT. Hepatitis B should not be regarded as a contraindication for LT. However, until an effective and readily available therapy is developed to prevent recurrence, HBsAg-positive patients should undergo transplantation under experimental protocols. Hepatitis C is also not a contraindication for LT. Although recurrent hepatitis C is usually mild and slowly progressive, severe forms of hepatitis requiring retransplantation have been increasingly reported. Long-term follow-up studies are needed to define the natural history of recurrent HCV infection after LT and its impact on allograft and patient survival.