HIV prevention through peer education and condom promotion among truck drivers and their sexual partners is described. Trends during an initial 18-month intensive phase, followed by a 24-month maintenance phase, were monitored with surveys. Trends for self-reported condom use were: increase among men (56 to 74%) during the first phase with a decrease (72%) during the maintenance phase. Respective figures for women were 51%, 91% and 70%. Multivariate analyses revealed that men most likely to report using condoms were unmarried, had children, were more educated, had previously reported a genital ulcer, and perceived themselves at risk for HIV infection (OR = 1.95-3.47). Women tending to use condoms were unmarried, aware of the limitations of condoms, not in denial as to the existence of HIV, harboured inaccurate information about HIV transmission and were afraid (OR = 1.35-2.52). Both sets of results suggest that the most sexually experienced men and women who did not have a permanent stable relationship and who perceived themselves at risk, were most likely to use a condom. Peer education was an effective tool for increasing knowledge and encouraging appropriate behaviour change. It was most effective as an intensive high-input intervention and sustainable with the relatively stable population of truck drivers.