The course of HIV infection has changed dramatically since the beginning of the epidemic. In Germany, 19 antiretrovirally active substances are available. They prevent viral penetration into the cell, inhibit the reverse transcriptase or the protease that are necessary to release infectious viral particles. According to German-Austrian therapy guidelines highly active antiretroviral therapy (HAART) should be started at the onset of HIV-related symptoms and/or when the CD4 cell count is < 350/microl. Patients should be treated in specialized centers because of the complexity of HIV infection and its management. For monitoring, CD4 cell counts and viral load are determined. Potential reasons for therapeutic failure include 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, 600-700 patients still die of AIDS every year.