We surveyed 420 paramedics employed by a large metropolitan fire department to determine the effects of educational seminars on their knowledge base, perceptions, and attitudes about AIDS and hepatitis B. All surveys were completed on an anonymous, voluntary, and confidential basis. Our educational efforts improved the paramedics' knowledge base concerning the medical manifestations of AIDS, identification of risk factors, modes of transmission, and means of infection control, but had no impact on paramedics' fear of contracting AIDS. While paramedics have a strong fear of contracting AIDS, we note that they underestimate their risk of acquiring hepatitis B. Only 17% of paramedics surveyed had received the hepatitis vaccine, despite attending an infectious disease seminar addressing the occupational risks of acquiring hepatitis B infections during the previous year. Further educational efforts to address the paramedics' attitudes about AIDS, as well as to encourage paramedics to recognize hepatitis B exposure as a significant personal health risk, are currently being pursued.