During the past three years the Clinical Neuropsychiatry Core has established a successful program for the recruitment, diagnosis, evaluation, retention, and longitudinal follow-up of appropriate research subjects for the CRC. We have shown, using strict criteria, that schizophrenia can indeed manifest for the first time after age 45. Our studies also suggest that, contrary to expectation, late-onset schizophrenia is likely to be primarily neurodevelopmental, rather than neurodegenerative, in origin. We have found that, in our outpatient population of older subjects with schizophrenia, aging and chronicity are not typically associated with diagnosable dementia, and may even occasionally lead to remission of symptoms. On the other hand, older schizophrenia patients have significant functional impairment. There are some similarities and some interesting differences among different late- onset psychoses (such as delusional disorder, psychotic mood disorder) that have, in the past, been lumped together under the term "paraphrenia." The primary aim of the Clinical Neuropsychiatry Core will be to continue to recruit, assess, and follow subjects for the CRC, using structured psychiatric interviews, standardized neurological and other medical evaluations and clinical rating scales. In addition to following subjects from the present CRC pool, we will recruit 350 new subjects during the period of CRC renewal. This Core will maintain liaison with assessments in other Cores, and refer appropriate patients to the Psychopharmacology Core for specific projects. The Core will continue to pay careful attention to and monitor diligently the quality of the diagnostic process. Inter-rater reliability will continue to be established and maintained by a highly structured training program which includes didactic and practice rating sessions on videotape and on live cases, and frequent retraining and reassessments of reliability. The Core will test hypotheses regarding demographic and clinical associations of psychosis in older patients, and examine relationships among the clinical variables obtained in this Core and selected measures from other Cores. In addition, this Core will generate pilot data for the development and testing of new hypotheses. Finally, the Core will provide training to Post-Doctoral (M.D., Ph.D., and Pharm.D.) Fellows, predoctoral and other trainees, and staff on clinical research assessment of older psychosis patients.