In spite of attempts to modify homosexual behaviour and the sharing of contaminated needles by drug abusers, AIDS virus infections continue to spread throughout the world. The potential for transmission, the lack of a vaccine and effective treatment, and the lethal nature of the disease cause great alarm and influence health care delivery. Dentistry is involved because oral health care is being given knowingly or unknowingly to high-risk individuals. These high-risk individuals are the sources for many other infections with viral, bacterial, fungal and protozoal organisms. In spite of the fact that spread does not occur through casual contact, concern is justified since many questions involving transmissibility and susceptibility have not been completely resolved. Therefore, dental professionals must follow infectious disease control guidelines to protect themselves as well as other patients. Because oral manifestations of those infected by the AIDS virus are common, dental professionals also play a role in recognition, counselling and referral.