Through a longitudinal study of 947 juveniles from the Florida Correctional Institution, the study focused on the psychological, social, and biological factors that distinguished violent from nonviolent offenders. The study also tested hypotheses derived from familial, social, psychological, and physiological factors associated with the various types. Data indicate that the violent offenders were more deviant than nonviolent criminals, and that within the violent sample the repetitively violent offenders were more deviant than those charged with but a single violent offense. The violent offenders were also assessed as being less employable and having more difficulties in interpersonal relationships than the nonviolent offenders. The differences in physical and mental health as well as in socialization and values were much less striking. Family and school variables were also important in distinguishing violent from nonviolent offenders. The violent and the repetitively violent had poorer achievement records and adjustment in school settings. The overall data pattern indicates that instigation to aggression and habit strength, interacting with situational variables, may be the primary determinants of whether a juvenile offender engages in violence, but measurably deficient controls, values, and socialization may be what determines which violent offenders become repetitively violent. Chapter tables, 126 references, and appended supplementary material