Infection with the human immunodeficiency virus is characterized by the destruction of the host immune system as also reflected by a progressive loss of CD4-positive T-cells. This finally results in the host's incapacity to deal with opportunistic infections and the immune surveillance of tumors, a clinical status known as the Acquired Immunodeficiency Syndrome (AIDS). The book AIDS Pathogenesis provides the reader with a complete overview of the clinical course of HIV-1 infection. It describes the clinical aspects of primary infection, the different clinical outcomes of HIV-1 infection, and strategies for anti-viral treatment. In addition, more fundamental aspects of HIV-1 infection are reviewed. These include the biology of the virus and the novel insights in AIDS pathogenesis. Not only is the significance of an HIV-specific cellular and humoral immune response discussed, but also the possible incapacity of the adult human host to deal with T-cell destruction. Finally, the book discusses the currently used laboratory markers that allow for monitoring of the clinical course of infection.