Detection and localization of hepatitis viruses in liver tissue are vital for diagnostic purposes and clinical management . Viral antigen detection, by immunochemistry (IHC), in liver biopsies is an attractive option for precise localization and quantification of viral proteins with direct access to histological patterns. This Intermediate Level course describes studies using IHC methods effective on fixed, archived specimens, including liver biopsies and surgical resection samples to analyze Hepatitis B and Hepatitis C.