We asked 39 physicians providing primary care for a mostly minority patient population to respond to a questionnaire concerning their attitudes and behavior toward AIDS risk assessment and preventive counseling and to indicate their beliefs concerning patients' knowledge and behavior. Most of the 36 physicians who responded (92%) agreed that physicians must educate their patients about AIDS. They also reported that patients who engage in risk-taking behavior may not know much about AIDS transmission and prevention. Despite these beliefs, these doctors reported that they gave advice to only 11% of their male patients and 14% of their female patients. More than one third of physicians reported feeling uncomfortable talking about patients' sexual preferences and practices. To identify patients at risk and to help prevent AIDS, methods must be found to make physicians more comfortable discussing sexual issues with their patients, especially their minority patients.