Each year, nearly 500,000 youth are detained in secure preadjudicatory detention facilities; and by some estimates, another 500,000 to 750,00 are held in adult jails and lockups awaiting trial. An examination of national trends in juvenile detention rates suggests that the number of juvenile preadjudicatory detainees has decreased over the past 20 years, but the length of time juveniles are held in secure facilities has increased over time. While most States have statutes relating to juvenile detention, many have no meaningful standards, and some have standards that are legally ambiguous and unclear. Many courts still follow the recommendation of the National Council on Crime and Delinquency which suggests that youth should be detained only if they are (1) likely to commit a new offense, (2) present a danger to themselves or the community, (3) likely to run away or fail to appear in subsequent court hearings, or (4) being held for adjudication in another jurisdiction. It is argued that that the broad legal or statutory grounds that permit broad discretion in detention decisions often reflect arbitrariness or capriciousness and are, subsequently, subject to abuses of power that harm juveniles legally. While little systematic evidence documents the harmful effects of standardless detention on youth, organizational and structural conditions of secure detention may have undesirable effects on staff-immate relations and on informal staff practices. It is concluded that preadjudicatory detention plays a discordant role in a system designed to provide care, protection, and rehabilitation for troubled youth. 12 discussion questions and 54 references. (Author abstract modified)