Routine hepatitis B vaccination beginning at birth was provided to Alaska Natives several years before other areas of the United States began routine infant hepatitis B vaccination programs. Follow up studies of hepatitis B immunity among Alaska Native children provide an early opportunity to assess long term protection against hepatitis B virus (HBV) infection for children vaccinated at birth with the currently used recombinant vaccine. This protocol describes an evaluation of long-term protection against HBV infection among children who received the recombinant hepatitis B vaccine beginning at birth, and who currently receive medical care at the Alaska Native Medical Center (ANMC) in Anchorage, Alaska.