This volume contains the proceedings of the ninth International Symposium on Retinal Degeneration, October 9-14, 2000, Durango, Colorado, USA. The chapters reflect a major emphasis on molecular genetics of retinal degenerations, particularly in the areas of candidate genes and in cloning and mapping. Significant animal models are described, as are several studies on macular degeneration. Studies on animal models, both vertebrate and invertebrate, continue to provide important new findings on the mechanisms of photoreceptor degeneration and cell death, as well as the means to retard, prevent, or reverse the degeneration by potentially therapeutic methods including transplantation, gene therapy, and survival factors. Diagnostic, clinical, cytopathologic, and physiologic aspects of retinal degenerations in human patients are also presented, as are several papers on structural, physiologic, and ageing studies in normal tissues that are important correlates for the study of retinal degenerations.