Hepatitis C virus (HCV) has been a major cause of post transfusion hepatitis, and is still an important cause of chronic liver disease throughout the world. How to treat patients with chronic HCV infection has been brought into focus in recent years, and a substantial amount of data has been obtained about the development of hepatitis C with and without treatment. This survey considers the diagnosis of hepatitis C, and present treatment modalities and their potential. The patients most likely to respond to treatment are described, and the authors finally discuss why treatment of hepatitis C still should take place in controlled studies.