Still, most HBV transmission and morbidity associated with acute hepatitis B occur among older adolescents and young adults, and most of these infections result from sexual transmission. Recommendations are long standing to vaccinate persons who report a history of multiple sex partners, those who receive treatment for a sexually transmitted disease, and men who have sex with men. However, vaccine is rarely offered in settings that provide health care to adults, and persons with high-risk sexual behaviors account for more than half of cases of newly acquired hepatitis B (Centers for Disease Control and Prevention. Unpublished data). Results of several studies indicate that health care practitioners do not routinely ascertain high-risk sex or drug histories from their patients and miss opportunities to inform and vaccinate persons at risk for hepatitis B (11–12). Even in settings that provide services specifically targeted to high-risk adults (such as sexually transmitted disease treatment clinics, HIV counseling and testing sites, and drug treatment programs), hepatitis B vaccination is not offered routinely (13).