The Clinical Core is key to the functions of the Indiana Alzheimer Disease Center. It recruits, evaluates, diagnoses and characterizes groups of patients with Alzheimer Disease (AD) and with other forms of dementia. Patients with familial AD are identified and referred to the Indiana ADC National Cell Repository. It refers appropriate patients and at risk family members to the new Genetic Counseling and Testing Core. Clinical Core staff train, teach health care providers and educate the lay public and particularly the African American communities. Data from the Clinical Core are analyzed with the assistance of the statistics component of the Administrative Core. Subjects are followed longitudinally to death. Autopsy and neuropathological examinations are obtained through the Neuropathology Core. A clinicopathological correlation consensus is reached. The Clinical Core has particularly emphasized obtaining biological samples from patients including lymphocytes, plasma and cerebrospinal fluid, all of which are banked. This cohort of clinically and genetically well characterized subjects that have biological specimens are used to support research projects to determine the effects of genotype on clinical phenotypes, age of onset, associated biochemical abnormalities and response to drug therapy. We have also characterized and sampled age matched normal controls using the same methods. These subjects and samples are a valuable resource in the search for biological markers that have specificity for AD. Eventual autopsy obtained through the Neuropathology Core will help validate diagnosis in these subjects and is essential to prove specificity of potential markers for AD. Patients from the Clinical Core have also participated in neuropsychological and neuroimaging studies, as well as in a large number of investigational drug trials. The Clinical Core has and will continue to support development of investigating of other non-AD dementias including unique large kindreds with Gerstmann-Straussler-Scheinker Disease and multisystems atrophy with presenile dementia. A large cohort of elderly African Americans are followed by the Clinical Core with many volunteers participating in a variety of investigational studies. We will continue a strong educational effort to engage the African American community to develop further support for our research projects and to better communicate the importance of medical research and autopsy in understanding the causes and treatment of AD.