The purpose of this project is to develop a new patient-centered outcomes methodology for chronic neurologic diseases which will eventually be used to develop practice guidelines for cost-effective and efficacious preventive treatment. This project will use multiple sclerosis (MS) as a model, and will apply a utility-based approach which integrates patient preferences, neurologic function, and societal cost in its evaluation of treatment trade-offs. This methodology requires validating a set of sensitive, reliable, and valid neurologic and patient-preference assessment tools, considering a series of societal cost models, and integrating them in the evaluation of clinical research on pharmaco- and rehabilitation therapies. The investigation will proceed in two phases. First, psychometric analyses will be done on preliminary versions of the proposed tools using available cross-sectional and longitudinal data. Second, data will be collected for two years from 230 MS patients undergoing pharmaco or rehabilitation therapies. Several health state models of societal cost will be used to evaluate the cost-effectiveness and -efficacy of these interventions. Future work will extend this -work to practice guidelines and to other chronic neurologic diseases.