Gene transfer has the potential to treat innumerable genetic and acquired diseases. Although viral vectors remain the most efficient means of gene delivery, further progress in understanding the fundamental biology of viruses, their special relationships with the host including mechanisms of infection, persistence, gene expression and immune evasion is required for successful virus-mediated gene therapy. Thus the focus of this meeting is to examine the host response, in particular the immune response, to viral infection and how to regulate it. The meeting will bring together immunologists, virologists and gene therapists to discuss this important aspect of gene therapy. The gathering of experts in fields of gene therapy, basic virology and immunology offers a unique opportunity to find solutions to new challenges in this field of regulating the host immune response to viral gene transfer. The design of this conference is to provide a detailed scientific overview of specific aspects of virus biology that relate to the immune response and the use of this knowledge to enhance effective gene delivery, resulting in successful gene therapy. Each session will have speakers with expertise in viral vectors, the host response to viral infection or immunology. In addition to the invited speakers per session, additional speakers will be selected from the submitted abstracts.