It has been well established that neuropsychological tests are useful in diagnosing brain lesions and differentiating various forms of dementia. However, while we can characterize specific cognitive impairments in patients with dementia, we are unable to predict the type of limitations the patient is likely to experience in his/her daily activities. Making such predictions is essential, particularly in the early stages of a dementing illness when the patient and the family need to know functional capabilities and limitations. The purpose of the current project is to further determine the relationship between neuropsychological test scores, actual everyday functional ability and caregiver burden in patients with Alzheimer's disease, frontotemporal dementia, and vascular dementia. An additional goal of this project is to determine whether the rate of cognitive decline can predict the rate of functional impairment in patients and the rate of caregiver burden/stress. These three patient groups are ideal to study since 1) they are among the most common forms of dementia in the elderly, and 2) they present with different cognitive strengths and weaknesses. Neuropsychological test and activities of daily living tests will be administered to patients, and a multidimensional caregiver burden instrument, psychiatric symptom questionnaires and a behavioral rating scale regarding the patient will administered to caregivers at two different test probes (separated by approximately 18 month intervals). The ability to predict functional limitations in patients, as well as burden of care experienced by caregivers based on the patients'neuropsychological test and behavioral scores will be assessed in each group of patients. Knowledge about these relationships will undoubtedly enable healthcare professionals to more effectively use neuropsychological results when planning treatment for patients, their caregivers and their families.