This paper first reviews the causes of overcrowding in juvenile institutions. Some factors identified are public policy that overvalues the effectiveness of juvenile institutionalization, the overuse of juvenile detention in the absence of rational criteria for detention decisions, the use of recidivism as a primary factor in the institutionalization of juveniles, the failure to develop and use alternative programs, and the absence of standards for juvenile institutionalization. The juvenile justice standards approved by the major national standards projects and the Juvenile Justice and Delinquency Prevention Act can reduce or eliminate overcrowding in juvenile facilities. Standards particularly relevant to these goals are standards for the decision to file, release, divert, or transfer juveniles; detention standards; standards for sentencing and appeals; standards for correctional facilities; and monitoring mechanisms. These standards' consistent presumption against unnecessary restraint, arrest, the institution of formal court action, detention, removal from the home, secure placement, institutionalization, and enhanced dispositions would reduce the populations in institutions. The restrictions against arbitrary decisionmaking and the insistence on strict accountability would also deter unjustified confinement. A 58-item bibliography