The authors propose a classification model of adolescent deviance that attempts to reconcile the unidimensional and multidimensional perspectives of delinquency development. The model suggests that adolescent deviance is composed of four major forms of deviant behaviors: overt or confronting (interpersonal violence); covert or concealing (property crimes); authority conflict or rebellion; and dangerous driving. These four major forms of adolescent deviance are composed of 10 types of deviant behavior: family rebellion, school rebellion, sexual activity, substance use, motor vehicle use, disorderly conduct, vandalism, interpersonal violence, fraud, and theft. These 10 types are operationalized through 61 deviant behaviors. The developmental perspective is introduced in this paper through the age of onset of each form and type of deviant behavior. This theoretical model was tested with an adjudicated sample of 656 adjudicated girls and boys from ages 12 to 18 (506 boys and 150 girls). They lived in the Montreal area of Canada and were adjudicated under the Canadian Young Offenders Act. The age of onset was used as a developmental indicator of deviance instead of measures of participation or frequency. The study used nine scales to perform three-level confirmatory factor analysis using the last year's frequency data. A four-level analysis was performed using 45 behaviors, 9 types and 4 forms of deviant behavior, and the general deviance construct. A group comparison procedure was used as an independent test of the general deviance syndrome. The analyses supported the existence of the construct of general deviance. There was no gender gap in the structure of the general deviance syndrome. Suggestions are offered for research that will test the model for 61 behaviors, 12 types, and 4 categories of deviance, as well as the latent construct. 2 tables, 5 figures, and 45 references