This outreach program uses intravenous drug abusers or other "street-wise" people to personally provide information about AIDS to other drug abusers and to motivate them to use risk reduction measures related to drug injection and sexual behavior. Initiated in two cities in Belgium in 1989, the snowball approach rests on a partnership between mental health agency professionals and drug users, based on the assumption that people from a cultural subgroup will be familiar with the cultural environment in which health behavior change is to take place. A collaboration among health services in different countries, the program operates in six cities in Belgium, Germany, and the Netherlands. The research gathered information on 60 variables relating to attitudes, risk behaviors, demographic characteristics, drug and sexual histories, and relationships to the prevention program. Results revealed variations in several variables, especially in contact with mental health services. Nevertheless, projects such as these offer hope that AIDS prevention efforts will extend beyond measures such as condom distribution and needle exchange. Table and 14 references