A study of children and adolescents (current N=100) with very early onset by age 12 (COS) of DSM-III-R defined schizophrenia with (97-M-0126) is examining the clinical, neurobiological, early neurodevelopmental, genetic, and clinical drug response characteristics of these cases. Earlier studies have documented the continuity between COS and adult onset cases (See Jacobsen and Rapoport, 1998 for review). The focus has now shifted to increasing the sample size and evaluation of familial risk factors including: psychiatric diagnoses of family members; smooth pursuit eye movements; neuropsychological tests deficits, and obtaining blood for cell lines for genetic studies (family members only, this is also covered under 96-M-0060, Dr. Ellen Sidransky).