The data for the analysis were gathered from 16 institutional units for both males and females. The comparative study of misconduct was based on the self-reports of youth, as well as on material from staff members, administrators, and field observers. The institutions varied in size, auspices, geographical region, and characteristics of the youth population (e.g., sex, age, race), so that the sample closely represented the variety of institutions for delinquent youth in the U.S. A total of 1,326 youths (85 percent of those surveyed) completed questionnaires; staff respondents numbered 645 (about half of the potential participants). The self-reports of the respondent delinquents indicated that misconduct was both frequent and pervasive; staff responses indicated underestimation of the inmate-reported misconduct. There were significant differences among the institutions in the amount of misconduct. Custodial programs had the highest rates of aggressive misconduct against other youth and staff (i.e., theft, staff assaults, fighting). Expressive misconduct (illegal drug use, fighting) was the highest in utilitarian programs. Youth in participatory programs reported the lowest frequencies of most types of misconduct. The perceived and actual deprivations of the institutionalized youth accounted for 18 percent of the variance in serious misconduct. Programs in which staff exercised rigid patterns of control and in which youth were unwilling to exert control over their peers had higher rates of participant misconduct than programs where the opposite patterns were in effect. Longer periods of confinement were found to further opportunities for misconduct. These findings indicate that participatory institutions seem better able to lessen the negative aspects of imprisonment and that utilitarian ones can better mitigate the effects of long-term confinement. Tabular data, appendixes, and a bibliography of about 220 items are provided.