To advance effectiveness research in mental health, we need common, standardized validated instruments that con be used easily in routine practice settings. The Schizophrenia Outcomes Module is a relatively brief, comprehensive instrument for monitoring and assessing the outcomes of treatment for schizophrenia in clinical care settings. The module was developed with the guidance of a multiinstitutional multidisciplinary expert panel; the clinical and theoretical considerations that framed the expert panel's deliberations and determined the module's content and characteristics are described. Initial field testing of the instrument involved longitudinal observation of 100 individuals with schizophrenia over a 6-month period. To our knowledge, it is the only brief and easily administered instrument that encompasses the four major outcome domains defined by the National Institute of Mental Health's Plan for Research on the Severely Mentally Ill. As such, it is a promising tool for effectiveness research in schizophrenia.