Since the hepatitis B vaccine was licensed in 1981, emergency physicians have had the opportunity to be immunized against the hepatitis B virus (HBV). The factors that affect the decision to undergo vaccination include the risk of acquiring an HBV infection in emergency practice, the prevaccination immune status of emergency physicians who have knowledge of their hepatitis serum marker profile, and the efficacy and safety of the vaccine. Emergency physicians have a significant risk of acquiring an HBV infection and are recommended by the Centers for Disease Control to receive vaccination. However, emergency physicians are often incidentally tested for HBV serum markers before immunization. Recent investigations have shown that seropositivity for hepatitis surface antibody (anti-HBs) does not necessarily preclude the need for immunization. Finally, experience with 750,000 doses has shown that it is a highly effective and extremely safe vaccine.