The authors describe trends in inpatient psychiatric length of stay (LOS) and admissions for the population of children and adolescents (N = 784) at the Menninger Clinic from 1988 to 1994. During this period. median LOS declined dramatically from 7 months to 3 weeks, whereas admissions increased 4-fold. The diagnostic case mix changed substantially, with a crossover in modal principal diagnosis from personality disorder to affective disorder. Use of medications became almost universal. Diagnosis and medication use became less important determinants of LOS over time. The practical implications of these patterns include higher patient turnover, fewer inpatient clinical contact hours, and heightened importance of continuity with outpatient care. Research should center on the impact of declining LOS on clinical and functional outcomes for children and adolescents.