AN EXTENSIVE DEFINITION OF DELINQUENCY, BOTH LATENT AND MANIFEST, AND A STUDY OF ITS DIMENSIONS WERE DEVELOPED TO CLARIFY STUDY RESULTS. TWO SAMPLE GROUPS, ONE MADE UP OF 825 ADOLESCENTS FROM MONTREAL SCHOOLS AND THE OTHER OF 470 WARDS OF THE STATE (AGES BETWEEN 12 AND 15), WERE INTERVIEWED AND ADMINISTERED A SELF-REPORT QUESTIONNAIRE ON 2 OCCASIONS IN 1974 AND 1976. THE DELINQUENT BEHAVIOR OF THE WARDS WAS INVESTIGATED FURTHER USING POLICE AND COURT REPORTS. RESULTS OF ANALYSIS SHOWED THAT LATENT DELINQUENCY WAS TRANSFORMED DURING ADOLESCENCE FOR SOME INDIVIDUALS FROM MALICIOUS ACTIONS AGAINST PROPERTY AND PERSONS INTO A HEDONISTIC DELINQUENCY MOTIVATED BY PRECOCIOUSNESS AND PLEASURE SEEKING. FOR OTHERS, ADOLESCENCE WAS LEFT BEHIND AS THEY ENTERED ADULTHOOD AND DEMONSTRATED A HIGHER LEVEL OF SOCIAL DEVELOPMENT AND PERSONAL MATURITY. ALTHOUGH WARDS OF THE STATE GENERALLY COMMITTED MORE DELINQUENT ACTS AND MORE SERIOUS OFFENSES, BOTH GROUPS OF SUBJECTS EXHIBITED EPISODIC AND UNPREDICTABLE DELINQUENT BEHAVIOR. THE ADOLESCENT APPEARS TO BE STRONGLY AND CONTINUALLY AFFECTED BY IMPULSE, OPPORTUNITY, INCITEMENT, AND SUGGESTION, IF THE STUDY RESULTS CAN BE GENERALIZED. IT IS CONCLUDED THAT DELINQUENT BEHAVIOR IN JUVENILES REFLECT THE CRISIS OF ADOLESCENCE, A MORE TUMULTOUS MANIFESTATION OF THE 'RITE OF PASSAGE,' WHICH WILL EVENTUALLY BE TEMPERED BY PROPER SOCIAL ORIENTATION. A THEORY BASED ON THIS ASSUMPTION IS CRUCIAL TO DELINQUENCY PREVENTION AND TREATMENT. EXTENSIVE GRAPHS AND TABLES ARE PROVIDED, AS ARE THE QUESTIONNAIRE, INTERVIEW FORM, OFFENSE CATEGORIES AND CODING SYSTEM FOR ANALYZING DATA. A BIBLIOGRAPHY IS PRESENTED. --IN FRENCH. (MHP)