AIDS: Advances in HIV therapy have greatly reduced the incidence of HIV-related complications and mortality, but co-infection with hepatitis C (HCV) virus is becoming more visible. The two infections share transmission routes, with injection drug users and transfusion patients the most commonly infected. Although sexual transmission is less common with HCV, it may be facilitated by an existing HIV infection. Effective HCV treatment strategies are urgently needed for people with HIV because it is leading to notable morbidity and mortality. Trial results of alfa interferon monotherapy are presented. The combination of interferon with Ribavirin also shows promise.