BTX has been used since the 1980s in support of the research mission of NINDS. Initial studies were focused on expanding the applicability of BTX treatment to movement disorders and exploring new indications. We evaluated the efficacy of an alternative serotype, type F. Under other protocols, we continue to study the physiology of movement disorders and BTX response. The application of BTX therapy to movement disorders requires an understanding of BTX preparation and handling. The treatment must be tailored to the disorder under treatment and to its expression in the individual patient. Users must know the specific techniques of injection, including the use of EMG and ultrasound guidance. This protocol allows us to train physicians in all aspects of the use of BTX. It also provides us with a cohort of patients, receiving a standard method of treatment and with a stable response to BTX injection, for participation in other protocols on movement disorders and on the responses to BTX injection.