In contrast to other countries in Southeast Asia, the HIV/ AIDS epidemic is in the initial stages in Viet Nam, although the rates have increased notably since 1997. This study examined attitudes towards the use of an HIV vaccine (when one becomes available) as a means for preventing the disease. Since injecting drug users are the great majority of those affected by the HIV/AIDS epidemic in Viet Nam, two focus groups (n = 18) were conducted among this population to identify potential barriers and incentives for HIV vaccination. Most were willing to be vaccinated if an HIV vaccine were available. Although there were some concerns about side effects, financial costs, and stigmatization, the benefits were seen to outweigh the risks. The findings may help governments better understand the potential demand for this type of vaccine and design social marketing campaigns for post-trial HIV vaccine dissemination in order to maximize potential uptake of an HIV vaccine. (Contains 1 table.)