Childhood antecedents of schizophrenia may variably reflect integral components of the schizophrenia diathesis, non-specific factors that potentiate this predisposition, or early manifestations of the disorder itself. This chapter explores the nature of the childhood antecedents of schizophrenia. It explores whether children who develop schizophrenia in adulthood are distinguishable from control children. The chapter examines how strong the association between the distinguishing features of preschizophrenia children as a group and the later development of the disorder is. It also explains ways we can identify preschizophrenia children on the basis of these characteristics. The early risk factors that flag the preschizophrenia status are also considered. Particular emphasis is on prospective population-based, high-risk, and follow-back studies. The measures investigated by the high-risk paradigm can aid in identification of truly vulnerable individuals within the high-risk population.