THE PATTERN of patient movement in mental hospitals appears to be shifting in the direction of earlier discharge for more and more patients. This policy of extensive and rapid discharge has been associated with a series of related phenomena: the increase in readmissions, in readmission rates, in multiple admissions for the same patient, and often, in multiple admissions for the same episode of illness. Because the majority of patients admitted to mental hospitals today are discharged in a relatively short time, this newer course of hospitalization has resulted in the decreased significance of biostatistical indices relating to patterns of retention and release of mental hospital patients. This focus of attention was of primary importance when patients were hospitalized for long (and more varied) periods of time and the readmission rates were low. At that time, it was reasonable to ask whether a given patient would