Human immunodeficiency virus infection continues to spread into selected populations at an unprecedented rate. Over 10 million individuals are already infected worldwide, and by the year 2000 as many as 30 million individuals may become infected. As a consequence, acquired immunodeficiency syndrome has become one of the leading causes of mortality in many urban centers worldwide. The predominant mode of transmission continues to be sexual contact, with increasing evidence of heterosexual transmission in the United State, western Europe, Latin America, and the Caribbean. In most cases heterosexual transmission is associated either with intravenous drug use or sexually transmitted diseases. With over 3 million infected women, perinatal transmission to infants has increased dramatically, and up to 5 million acquired immunodeficiency syndrome orphans now exist in Africa alone. In order to control further spread of this disease, educational campaigns encouraging behavioral change are underway. Although these programs have had initial successes, there is now increasing evidence of recidivism in selected high-risk groups, emphasizing the need for repeated intensive counseling in order to sustain behavioral changes.