The Clinical Core has characterized, followed and provided subjects and data, and has collected and banked biological specimens that have contributed to much research progress in the past 25 years in areas such as early and accurate diagnosis of AD, tracking the course of dementia, and testing new treatment approaches for AD. The Specific Aims are: (1) Maintain and follow a panel of 400 well characterized English-speaking subjects with Alzheimer's disease (AD), dementia with Lewy bodies (DLB), Parkinson's Disease with Dementia (FDD), Mild Cognitive Impairment (MCI), and age- and education-matched healthy control subjects. (2) Maintain and follow a panel of 100 well characterized Spanish and English-speaking Hispanic subjects with Alzheimer's disease (AD), dementia with Lewy bodies (DLB), Parkinson's Disease with Dementia (PDD), Mild Cognitive Impairment (MCI), and age- and education-matched healthy control subjects through our Hispanic Initiative. (3) Maintain a high autopsy rate (i.e., greater than 70%). (4) Perform annual detailed and standardized nursing, neurological, and neuropsychological evaluations of all subjects. (5) Maintain and augment banks of plasma, DNA, and CSF from subjects with AD, MCI, and healthy controls. (6) Share clinical data with the National Alzheimer's Disease Data Coordinating Center (NACC) Uniform Data Set (UDS) and with investigators performing other multi-center analyses of clinical data. (7) Participate in projects with other ADCs (e.g., NACC), in ADNI, and in multi-center therapeutic drug trials for AD. (8) Refine and evaluate clinical and neuropsychological assessment procedures for accurate identification of MCI and the transition to AD in very mildly impaired subjects. (9) Refine and evaluate clinical, neuropsychological, and laboratory assessment procedures for the accurate differentiation of AD from DLB, PDD, Frontotemporal dementia (FTD), and other dementing disorders. (10) Coordinate activities such as autopsy procurement and education with other Cores. RELEVANCE (See instructions): AD affects millions of Americans with its risk growing exponentially with age. The AD Centers Program fosters research related to AD and non-AD dementias. The ADRC will enhance the performance of innovative research on AD and related topics, including research that may lead to potential disease modifying therapies or behavioral treatments. It will provide an environment and core resources to enhance research, foster professional and community training, and coordinate interdisciplinary research.