Mother-to-child, or vertical transmission, of hepatitis C virus is now the dominant mode of acquisition of infection for children. The rate of transmission is low in women who are not also HIV-positive. Whether the mode of delivery is associated with transmission remains questionable; breast-feeding does not appear to be a source of infection. The detection of hepatitis C virus RNA using the polymerase chain reaction is a sensitive method for the early diagnosis of infection in perinatally exposed infants, but false positive results can occur. The natural history of hepatitis C virus infection in children is not well defined, but chronic infection is common in most cases. The disease progression is slower than in adults. Therapeutic trials (not placebo controlled) in a small number of children suggested a sustained response to interferon treatment in only a minority of cases. The option of combination therapy with ribavirin looks promising and needs evaluation.