Screening of blood products and attention to stricter infection control measures in hemodialysis units have reduced the incidence of hepatitis C virus (HCV) infection among dialysis patients. HCV can be transmitted via transplanted organs. Renal transplantation may accelerate the course of liver disease, which has an impact on patient and graft survival. Interferon (IFN) alfa monotherapy has produced promising results during treatment but disappointing long-term results in patients with HCV-associated glomerulonephritis. Dialysis patients with HCV infection respond well to IFN-based therapy, and there appears to be clinical benefit in clearing HCV in renal transplantation candidates. Larger prospective trials are required to fully determine the role of IFN in these patient groups, including the potential use of IFN plus ribavirin and pegylated IFNs. IFN therapy in renal transplantation patients is not recommended because of potential graft rejection.