As the population ages in the United States and other countries, we will be confronted with an increasing number of patients with neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease. The progressive cognitive impairment that characterizes Alzheimer's disease leaves patients increasingly unable to care for themselves. Patients with Alzheimer's disease also are prone to dementia-related behavioral disturbances, which can range from annoying (such as repetitive questioning) to disturbing (such as vocal outbursts) to dangerous (such as hitting and pushing).