Natural history and treatment outcome of disease are of critical importance to patients, clinicians and health care providers across the full range of medical disciplines. In many specialties, such as neurology and neurosurgery, this sort of information can be hard to obtain in the absence of extensive outcome studies and agreed measures of outcome in different conditions. This volume seeks to help inform about effective care and rehabilitation by providing a succinct review of whatever data is available for the majority of conditions encountered in clinical practice. Particular attention has been given to the evaluation of the severity and outcome of each disorder and to advise on comparing risks and benefits of treatment. This resource will prove invaluable to all involved in informing patients of treatment options and making important cost-efficient decisions on care. It should also be welcomed in the planning of clinical trials for potential new therapies and as a reference in medicolegal spheres.