The importance of psychological and biological factors in the explanation of deviant behavior has long been eschewed by criminologists. Indeed, Gottfredson and Hirschi, two prominent criminologists who have helped mold the shape of criminological research, contend that self-control is the only personal characteristic involved in criminal deviance. However, other researchers, namely Moffitt and Rowe, suggest that although self-control is an important explanatory factor in the study of deviance, so are neuropsychological and physiological factors. The current study engaged in a comparative analysis of 78 adolescents attending public high schools in Northern California and 105 adolescent offenders incarcerated in the California Youth Authority to explore how self-control, neuropsychological, and biological factors interrelate to distinguish offenders from nonoffenders. Participants completed self-report questionnaires probing demographic variables and intelligence, resting heart rate was recorded, and neuropsychological functioning was measured using the Cambridge Neuropsychological Test Automated Batteries (CANTAB). Results indicated that juvenile offenders had lower resting heart rate, evidenced poorer performance on tasks mediated by the prefrontal cortex, and scored lower on measures of self-control. Results of regression analyses further indicated that biological and neuropsychological factors, as well as self-control, distinguished the offenders from the nonoffenders. The findings underscore the importance of integrating more biological and neuropsychological perspectives into criminological theories. Tables, references