PIP: HIV/AIDS and iv drug use (IVDU) are of significant multinational scope and growing. Supporting increased IVDU in many countries are countries' geographical proximity to illicit drug trafficking distribution routes, law enforcement efforts which increase the demand for more efficient drug distribution and consumption, and countries' infrastructural and social modernization. Given the failures of intensified law enforcement efforts to thwart the use and proliferation of illegal drugs, countries with substantial IVDU should look away from preventing use to preventing HIV transmission within drug user populations. With HIV seroprevalence rates rapidly reaching 40-50% in some developing country IVDU groups, a variety of prevention programs is warranted. Such programs should be supported and implemented while prevention remains feasible. This paper examines the variation in HIV seroprevalence among IVD users, rapid HIV spread among users, HIV among IVDUs in Bangkok, emerging issues in HIV transmission among IVDUs, non-AIDS manifestations of HIV infection among IVDUs, prevention programs and effectiveness, and harm reduction.