This is the first of two reports of an investigation of predictors, diagnostic criteria, and outcome characteristics in 111 psychiatric admissions. Most of the patients would be considered schizophrenic by many criteria. Evaluation of outcome characteristics of this cohort indicates that outcome dysfunction is best considered as a continuum. The different areas of outcome dysfunction: work, symptoms, social relations, and duration of nonhospitalization, seem to operate as open systems, all partly interrelated and affected by psychiatric disorder but each area also affected by variables more specific to it alone. Although several diagnostic and classification systems were evaluated, the differences in outcome among different diagnostic groups were less striking than is often expected. These results indicate that outcome is a complex phenomenon, and that the ability of a diagnosis to predict a specific outcome has often been overstated.