This chapter deals with the developmental theories of schizophrenia to provide a foundation for a discussion of functional brain imaging studies of childhood-onset schizophrenia. Neurochemical brain imaging methodologies have permitted testing of the dopamine hypothesis of schizophrenia. Clinical studies have demonstrated prominent premorbid developmental delays in childhood-onset schizophrenia, especially in the areas of speech and language. Neurobiologic studies of the NIMH childhood-onset schizophrenia sample have generally supported neurobiologic continuity between childhood- and adult-onset schizophrenia. Very few functional brain imaging studies have been conducted in patients with childhood-onset schizophrenia. The only study of cerebral glucose metabolism in childhood-onset schizophrenia has been conducted with a subset of the National Institute of Mental Health (NIMH) childhood-onset schizophrenia sample. The finding of cerebellar hypermetabolism in childhood-onset schizophrenia, seen with both data analytic approaches, is notable in light of recent evidence implicating the cerebellum in higher cortical processes.