This proposal seeks support for the fifth bi-annual meeting on Human Gene Therapy to be presented by the Cold Spring Harbor Laboratory from September 25-29, 2000. This is one of the major Cold Spring Harbor meetings and will bring together in the intensive and highly interactive style characteristic of Cold Spring Harbor meetings the basic scientists who are developing the tools for efficient, targeted and safe transfer of therapeutic genes in humans and clinicians who are characterizing and treating human disease. The meeting will be divided into 8 presentation sessions and three poster sessions. The meeting will cover topics of current relevance to both the ex vivo in in vivo approaches to human gene therapy, including the design of efficient viral and non-viral gene transfer reagents, the characterization of transgene expression and gene regulation, techniques for stable and efficient transplantation of genetically modified cells, the development and study of relevant animal disease models and the design, implementation and results of human clinical trials. Presentations will include talks by recognized leaders in the field of human genetics, molecular virology and gene therapy as well as by speakers to be selected from the submitted abstracts. The audience for this meeting, like all major Cold Spring Harbor meetings, is a world-wide audience of senior investigators, research fellows and students in human and molecular genetics, virology, developmental biology, regulation of gene expression, the development of animal models and clinical medicine. Participation by younger, less well established investigators in the proposed meeting will be encouraged, and wherever possible, high quality abstracts by women scientists will be selected. Funds provided by the NIH through this grant will partially support travel, registration and housing for invited participants and a number of other participants selected from submitted abstracts, depending on the need of the participants and the level of financial support obtained for the meeting. We anticipate the attendance of about 450 (the maximum allowed for Cold Spring Harbor Laboratory meetings) scientists from laboratories around the world.