This analysis explores the similarity between peer educators and their contacts. To examine interpersonal communication in the context of peer education, this study tested a new approach using multiple semi-structured interviews and network analysis to collect data from 106 peer educators and 526 of their contacts. These evaluation activities were conducted at three sites in Ghana during April 1998, in peri-urban and rural locations, and in in-school and out-of-school targeted settings. It was found that in their peer counselling and peer promotion activities peer educators tend to reach people who are like themselves (53% within 2 years of age, 59% same sex, 70% same ethnicity, and 65% same school status) however, this trend is not uniform among all youth and varies by demographic characteristics and their cultural environment. By examining the social networks of peer educators, it is possible to gain a better understanding of the process of peer education counselling in the context in which it occurs. The study also shows that controlling for other factors, contacts of peer educators who are highly similar regarding age, sex, ethnicity, and school status, are 1.74 times more likely (95% CI: 1.18, 2.56) to have done something to protect themselves from AIDS in the past three months. The results have relevance for programme managers and planners, researchers, and international agencies serving youth.