In the Western Pacific Region mother-to-child transmission at birth plays a very important role in hepatitis B epidemiology. Approximately 3% to 5% of infants born in the Region will acquire chronic hepatitis B infection at birth if not immunized immediately after delivery. It is hoped that these guidelines for developing and implementing operational strategies for increased coverage of the first dose of hepatitis B vaccine within 24 hours of birth will help reduce mother-to-child transmission of the disease.