Each year, an estimated 20,000 infants are born to women in the United States who are positive for hepatitis B surface antigen (HBsAg). These infants are at high risk for perinatal hepatitis B virus (HBV) infection and for chronic liver disease as adults. To identify newborns who require immunoprophylaxis to prevent perinatal HBV infection, all vaccine advisory groups have recommended routine HBsAg screening of all pregnant women during an early prenatal visit in each pregnancy. Federal funding to support perinatal hepatitis B-prevention programs became available in 1990, and by 1992, programs had been implemented in all 50 states and the District of Columbia. Specific objectives of these programs are to ensure that 1) all pregnant women are tested for HBsAg, and 2) infants born to HBsAg-positive women receive hepatitis B immune globulin (HBIG) and hepatitis B vaccine at birth, with follow-up doses of vaccine at ages 1 and 6 months. This report describes the case-management features of successful hepatitis B-prevention programs in Connecticut during 1994-95 and in the United States during 1994.