From the standpoint of the surgical pathologist “hepatitis” is defined as the set of histologic patterns of lesions found in livers infected by hepatotropic viruses, by non-hepatotrophic viruses leading to liver inflammation in the context of systemic infection, or due to an autoimmune disease, drug, or toxin involving the liver. This article is centered on the histologic patterns of injury in acute viral hepatitis, encompassing the hepatotropic viruses A, B, C, D, and E and the “icteric hemorrhagic fevers” (dengue, hantavirus, yellow fever). A brief mention of viruses causing hepatitis in immunosuppressed patients also is presented.