Photoreceptor cells are a highly specialized cell type in the eye. They capture light and transform the light signals into chemical signals that are delivered to other types of neurons in the eye. Vision is thus initiated by photoreceptors and relies completely upon proper photoreceptor survival. In many inherited diseases that lead to blindness, the disease gene directly affects photoreceptor cells. One such disease, retinitis pigmentosa (RP), has disease genes that directly affect rods, the photoreceptor type that mediates vision in dim light. People born with RP are thus night blind. Subsequent to rod dysfunction and death, the cone photoreceptors, which mediate color and daylight vision, also lose function and die. We have suggested a model wherein cones are affected due to dysregulated metabolism, which occurs after rods die. Cones do not express most RP disease genes, but they do experience a greatly altered environment following rod death. The outer segments of the cone collapse lose their intimate association with their support cells and are exposed to a hyperoxic environment. We have begun to develop gene therapy to combat some of these problems. Our approach is to use adenovirus-associated vectors (AAV) to deliver genes that help cones fight oxidation and other forms of stress. Our progress in treating RP mice using such vectors will be presented.