Fourteen-fifteen year olds throughout the eastern Bay of Plenty were tested for hepatitis B surface antigen (HBsAg) and antibody (anti-Hbs). Overall 44.7% showed evidence of infection with hepatitis B, and 9.2% were HBsAg positive, rates being higher in Maoris and in males. Maori rates were very similar through most of the region, with greater variation amongst Europeans. However, the infection rates are very high in all groups and areas, confirming that hepatitis B is highly endemic throughout.