This book will contain the proceedings of the XV International Symposium on Retinal Degeneration (RD2012). A majority of those who will speak and present posters at the meeting will contribute to this volume. The blinding diseases of inherited retinal degenerations have no treatments, and age-related macular degeneration has no cures, despite the fact that it is an epidemic among the elderly, with 1 in 3-4 affected by the age of 70. The RD Symposium will focus on the exciting new developments aimed at understanding these diseases and providing therapies for them. Since most major scientists in the field of retinal degenerations attend the biennial RD Symposia, they are known by most as the 'best' and 'most important' meetings in the field. The volume will present representative state-of-the-art research in almost all areas of retinal degenerations, ranging from cytopathologic, physiologic, diagnostic and clinical aspects; animal models; mechanisms of cell death; candidate genes, cloning, mapping and other aspects of molecular genetics; and developing potential therapeutic measures such as gene therapy and neuroprotective agents for potential pharmaceutical therapy. While advances in these areas of retinal degenerations will be described, there will be many new topics that either were in their infancy or did not exist at the time of the last RD Symposium, RD2010. These include the role of inflammation and immunity, as well as other basic mechanisms, in age-related macular degeneration, several new aspects of gene therapy, and revolutionary new imaging and functional testing that will have a huge impact on the diagnosis and following the course of retinal degenerations, as well as to provide new quantitative endpoints for clinical trials. The retina is an approachable part of the central nervous system (CNS), and there is a major interest in neuroprotective and gene therapy for CNS diseases and neurodegenerations, in general. It should be noted that with successful and exciting initial clinical trials in neuroprotective and gene therapy, including the restoration of sight in blind children, the retinal degeneration therapies are leading the way towards new therapeutic measures for neurodegenerations of the CNS. Many of the successes recently reported in these areas of retinal degeneration sprang from collaborations established at previous RD Symposia, and many of those will be reported at the RD2010 meeting and included in the proposed volume. We anticipate the excitement of those working in the field and those afflicted with retinal degenerations will be reflected in the volume.