The list of potential hepatotrophic viruses continues to grow, with the recent discovery of the GB virus-C, the TT virus, and the SEN virus. Prevalence rates of the GB virus-C have ranged from 1.2% to 13% among healthy blood donors from all over the world. Higher prevalence rates have been reported among intravenous drug users. Similarly, the TT virus has a global distribution. However, in spite of numerous reports of the presence of both of these viruses in various kinds of liver diseases, definite evidence linking it to a specific disease or illness is lacking. The SEN virus is thought to be a novel viral agent that may be linked to cryptogenic chronic hepatitis, but data are awaited.