Prospective developmental data on 33 children of consensus diagnosed schizophrenic parents were compared to control samples of children of other psychiatric patients and children of normal parents. Contrary to several reports, the children of schizophrenics, observed from birth to age seven, were remarkably normal on a host of pregnancy and delivery variables, neurological examinations, physical growth measures, and psychological tests. However, a combination of three indicators characterized five of the 116 children, and all five were offspring of schizophrenics (17 per cent of the high risk sample), thus matching the expected lifetime risk for schizophrenia previously observed in such samples. Case histories show that all five children have enduring patterns of maladjustment and exhibit behaviours often reported in the premorbid histories of schizophrenics. Most have family histories heavily loaded with schizophrenia. In terms of a diathesis-stress model, these five children appear especially vulnerable to future schizophrenia in the absence of rational methods of prevention.