Low parental monitoring is a well-established risk factor for and presumed cause of teen problem behavior. However, an integrated theory for how monitoring changes teen behavior has not been articulated. We propose a model in which parental monitoring can reduce teen misbehavior via nine mechanisms organized into behavior-management (B), context-control (C), and relationship/support-mediated (R) domains (BCR model). Parental monitoring increases the expectation and actual occurrence of punishment for misbehavior (B), enables the parent to steer the teens’ socialization contexts (peers, nonparent adults, siblings, media) away from those that encourage misbehavior (C), and strengthens the teen’s bond to parent, disclosure of information, and receipt of social support (R)—all of which in turn reduce misbehavior.