Intended for personnel in programs serving persons with developmental disabilities, the booklet provides basic information about the major psychiatric disorders and their treatment. Five sections cover: the major disorders; medications--uses and problems; assessment; cooordination of services; and psychiatric emergencies. Major disorders such as schizophrenia and affective illness, bipolar disorder, and depression are described. Commonly used antipsychotic and antidepressant medications are listed by both generic and trade names, and side effects are explained. Four steps of assessment are recommended: (1) obtain informed consent from the client or guardian; (2) obtain medical and psychiatric history; (3) obtain a social history; and (4) obtain verification that the client has had a recent physical examination. Coordination of services including those of a physician, a therapist, a source of expert information on medications, and an inpatient facility is urged. Finally, appropriate immediate management of a psychiatric emergency is discussed. Six references. (DB)