The criminological study of juvenile delinquency under discussion, for which the authors claim rigorous scientific accuracy, views juvenile delinquency as the result of the interaction of biological, psychological, and sociological factors within the conceptual framework of a circular, rather than linear, causality. The theoretical basis of the entire study is, however, longitudinal causality, and temporal dimensions are introduced into the analysis of the juvenile delinquency phenomenon, viewed as determined by the strength or weakness of the adolescents' social ties (e.g., with family, school, church, part-time employers, friends) and such personal traits as social maladjustment, aggression, and psychoses). A random sampling of 825 Montreal high school students, aged 12 to 16, were surveyed in 1974 by means of a self-administered test, consisting of questions on their families, school environments, leisure activities, friends, and hidden delinquency acts. The delinquency acts considered included adult-type legally criminalized acts and juvenile status offenses. The same survey subjects were retested by the same method in 1976 when their ages had increased to 14-18. The findings confirmed well-established criminological theories (e.g., linkages between delinquency and weak or non-existent social ties, social handicaps, and mental illness). The theoretical premises and the methodology used, leading to a view of delinquency as an epiphenomenon of adolescence, lack the rigorous scientific quality claimed by the researchers. The data gathered through the Montreal survey are not questionable, only their interpretation is doubtful. Etiological considerations, not warranted by the research design, were introduced in a sudden shift of research levels, further weakening the study. Footnotes contain bibliographic references.