This study examined how differences in infection control procedures and patients' perceived knowledge of infection control, and how AIDS and hepatitis might affect attitudes toward the use of such measures. Patients receiving treatment at two sites where the methods of infection control and the frequency of their use differed (dental school and private dental practices) were surveyed concerning their approval/acceptance of infection control measures and self‐report of knowledge concerning infectious disease and possible transmission of infectious disease during dental treatment. Data were collected from 379 patients, 272 from the dental school and 107 from five private practices. A high percentage (95 percent) of both dental school and private patients felt they were adequately protected, while fewer than 2 percent expressed anxiety about infection control procedures being used in either setting. Factors such as gender, age, and years of formal education did not significantly affect attitudes toward infection control measures, but age and education were correlated with perceived knowledge of infectious diseases. Patients' reported knowledge of infectious disease had a significant effect on their decision to leave a practice if the dentist was HIV positive. A significantly higher percentage of dental school patients felt that barrier infection control techniques should be used routinely. Patients treated where such techniques were not routinely used nevertheless expressed satisfaction with that level of protection, implying that patients tend to accept the level of infection control being practiced where they receive treatment.