We know that the risk to health-care workers of acquiring HBV infection in the health-care setting is greater than that of acquiring HIV infection. We know that blood is the primary concern and that the risk following needlestick injury or a cut involving exposure to blood from an HIV-infected individual is approximately 0.5%. We know that transmission can occur without such injuries, but that the risk of such transmission is lower than after a needlestick or cut. We know that many exposures are preventable and that new prevention strategies and technologies are needed. We need to know the risk of infection in groups of health-care workers with extensive blood exposures, whether alterations in the design of devices can reduce the risk of needlesticks and other injuries, and the optimal strategies for ensuring compliance with recommendations.