This retrospective study describes characteristics of 770 psychiatric inpatients in a medical center during a one year period. Information collected on the inpatients’ included sex, age, marital status, diagnosis, days of stay, the circumstances of admission, and the circumstances of discharge and readmission if they occurred during the one-year period. The results show that there were two ages when admission peaked. The majority of psychiatric disorders were mood disorder and schizophrenia. A significant age difference was found between inpatients diagnosed with these two disorders. Geriatric patients had a large proportion of organic mental disorders. Hospitalization was longer for inpatients with schizophrenia than for those with either neurosis or substance abuse. Neither sex nor age affected the days of stay. In the one –year period the rate of discharges against medical advice (DAMA) was 15%, and the rate of readmission was 24%. Eight percent of the patients who were discharged were transferred to other institutions. Other analyses and comparisons with previous reports are included in this article. The need for further epidemiological and hospital utilization studies to provide essential data for rational planning of psychiatric services and reimbursement is emphasized.