Schizophrenia in children is diagnosed by using adult criteria. Based on the age of onset, patients with childhood onset schizophrenia (COS) are subdivided into those with very early onset (before age 12-14 years) and those with early onset (between 14-17 years). The prevalence of COS is reported to be 1 in 10,000 before the age of 12 years; however, there is a significant increase around puberty and early adolescence and by 18 years of age, 20% of the patients with schizophrenia will have the illness. Simple delusions and hallucinations revolving around childhood themes, language and communication deficits and flat affect have been reported in COS. Follow-up studies suggest that the outcome is generally poor to fair. Predictors of poor outcome are age of onset (less than 12 years), insidious onset and marked premorbid abnormalities. (Contains 1 table.)