The Overall Goal of the MADRC Clinical Core is to establish and maintain a cohort of men and women of diverse ethnic and racial backgrounds who will join us in conducting research into the cause, prevention and cure degenerative brain diseases. The composition of the cohort, which we call the Longitudinal Cohort on Brain Aging and Dementia, will include elderly individuals with normal cognition, individuals with mild cognitive impairment and other mild deficits, and individuals with a range of dementias including Alzheimer's disease, Lewy body diseases (including Parkinson's disease, Parkinson's with dementia and dementia with Lewy bodies), and frontotemporal dementia. The composition of this cohort will enable us to detect the earliest cognitive and behavioral changes associated with Alzheimer's disease and related dementias and to track their evolution over time. The cohort will also serve as a reservoir of individuals who are interested and willing to participate in local and national research projects. The Specific Aims of the Core are to: 1) Recruit into the Longitudinal Cohort 600 individuals spanning the spectrum of cognition from normal elderly to mild cognitive impairment to dementia;2) Examine these individuals with comprehensive assessments that include the full Uniform Data Set, which are submitted to NACC;3) Establish a Genetics and Biomarker Program to collect and store biological fluid samples for biochemical, molecular and genetic studies;4) Expand the Neuroimaging Program to archive all MR and PET scans on Cohort subjects and to support ongoing projects within the MADRC;5) Characterize the neurological, psychiatric and neuropsychological features of all Cohort participants annually, and link these data to their collected biomarker and neuroimaging data;6) Refer Cohort participants to specific research projects within the MADRC and to national ADC and other multi-site investigations;7) Facilitate brain autopsies and, working with the Neuropathology Core, direct clinical-pathological correlations;8) Train new investigators in dementia research;and 9) In concert with the Education and Information Core, promote dementia awareness among lay and professional groups and offer research opportunities to underserved minority groups. RELEVANCE (See instructions}: Developing cognitive impairments and frank dementia are among the most feared consequences of aging. Staffs in the Clinical Core of the MADRC are dedicated to partnering with men and women who will join us in research studies into the causes, course, treatment and eventual prevention of dementia.