The course of HIV-infection has changed dramatically since the beginning of the epidemic. Opportunistic infections and AIDS-defining tumors are diagnosed less frequently since the introduction of antiretroviral therapy and the time of survival has increased. According to German-Austrian therapy guidelines highly active antiretroviral therapy (HAART) should be started on the onset of HIV-related symptoms and/or when the CD4 cell count is lower than 350/microl. Patients should be treated in specialized centres because of the complexity of HIV-infection and its therapy. For monitoring CD4 cell counts and viral load are determined. Reasons for therapeutic failure can be drug interactions, resistance or compliance problems. Although HIV-infection is often compared to insulin dependent diabetes mellitus psychological and social impact on HIV patients is still high. Increasing viral multi-drug resistance, long-term toxicity like lipodystrophy, osteoporosis and cardiovascular disease are only some problems HIV-infected patients are facing in the next years. In Germany 600 to 700 patients still die because of AIDS every year.