Viral hepatitis poses important problems for children. In preschoolers, hepatitis A virus (HAV) infection frequently causes acute liver failure. Vaccinating toddlers against HAV in countries with high endemicity is expected to decrease mortality. HAV vaccine demonstrates efficacy (comparable to immunoglobulin) as post-exposure prophylaxis. A recently developed vaccine against hepatitis E virus (HEV) may benefit fetal health, because pregnant women are most prone to acute liver failure as a result of HEV. Hepatitis B vaccine continues to demonstrate value and versatility for preventing serious liver disease. With chronic infection, undetectable levels of serum HBV DNA complement e-seroconversion as the preferred outcome measure; suppressed viral load correlates with long-term complications better than HBeAg status. Among Taiwanese children, low pretreatment HBV DNA (<2 x 10(8) copies/ml) strongly predicted response to interferon-alpha. Future paediatric studies must incorporate HBV DNA levels. The rationale for routine treatment of immunotolerant hepatitis B during childhood remains uncertain. Any treatment of chronic hepatitis B in childhood requires consideration of the risks and benefits. Childhood hepatitis C virus (HCV) infection results mainly from mother-to-infant transmission. Babies of HCV-infected women should be tested for serum HCV RNA at 1 month of age. If negative, confirmatory anti-HCV antibody testing may be performed between 12 and 15 months of age. Children with chronic hepatitis C may develop progressive fibrosis/cirrhosis, particularly in the setting of obesity and insulin resistance. Treatment of children chronically infected with genotype 2 or 3 is highly successful: combination therapy of pegylated interferon-alpha and ribavirin is well tolerated and superior to pegylated interferon-alpha alone.