Dendritic cells are vital to induce potent anti-viral immune responses. It will become clear to the reader that dendritic cells often play a dual role during viral infections. On the one hand they are able to mount potent antiviral immune responses, and on the other hand several viruses, including HIV-1, use DC as a vector to be transferred from the periphery to the lymph nodes where they infect their prime target. Dendritic cells (DC) are vital to induce potent anti-viral immune responses. However, viruses have developed a large number of different escape mechanisms in order to overcome the host immune system. A prime target in this respect are DC, since they are the only antigen presenting cell able to induce also naive T cells. In the present CTMI-volume the interaction between several viruses, including HIV-1, SIV, EBV, measles virus, LCMV and HSV-1, with DC will be described and discussed. It will become clear to the reader that DC often play a dual role during viral infections. On the one hand they are able to mount potent antiviral immune responses, and the other hand several viruses, including HIV-1, use DC as a vector to be transferred from the periphery to the lymph nodes were they infect their prime target cells. In the second part of this volume several DC specific immune intervention strategies will be presented. This includes topics such as DC vaccination strategies in immunotherapy, viral vectors for the genetic modification of DC and cross presentation of virus infected cells by DC.