The occurrence of changes in association with the administration of mepazine (Pacatal) to 101 schizophrenic inpatients has been studied. These patients were functioning in the community prior to their admission. Changes considered as improvement within the ward milieu during the period of drug administration occurred in association with effects of the drug in 25 patients. Thirty-four patients experienced improvement in their interpersonal transactions in the ward milieu in the absence of association with drug effects. A somewhat consistent group of interpersonal changes appeared in some patients in association with the drug effects. These data suggest further study of the interpersonal effects, problems and usefulness of these behaviors. The effects associated with the drug offered utility in some of the patients in the therapeutic milieu of the psychiatric unit studied.