Conflict has traditionally been thought to contribute to the epidemic spread of HIV. New data call into question this assumption, and there is concern that the 'post-conflict phase' may be a particularly dangerous time for HIV transmission. The post-conflict phase is characterized by a potentially disastrous confluence of factors including demobilization of combatants, the presence of peacekeeping forces, the return of potentially infected soldiers and refugees, high-risk behaviours and persistent economic and social debilitation. These factors, along with the concentration of populations into cities and urban areas, may further increase the risk to these populations of HIV infection. Further research and study are required to adequately inform and address the issue of HIV transmission in post-conflict societies.