PROJECT SUMMARY Early alcohol use is associated with many negative psychosocial and health outcomes and delaying initiation of drinking and promoting effective harm reduction remains an important public health goal. Parents are an early potent source of alcohol socialization. Though parental modeling of drinking has been studied extensively, much less research has considered other ways in which parents socialize youth about alcohol (alcohol-specific socialization). This proposal focuses on prevalent modes of alcohol-specific socialization, discussions about the risks of alcohol and sipping/tasting alcohol with parental supervision. An alarming finding is that these modes of parental alcohol-specific socialization are not uniformly protective, and in fact, can increase risk for drinking. It is critically important to understand the reasons underlying these unexpected findings as this has enormous implications for guidance provided to parents. Interpersonal interactions are the medium through which parent socialization operates, and we propose that it is necessary to consider the quality and nature of parent-adolescent dyadic interactions to fully understand parent alcohol-specific socialization and harm reduction efforts. This study builds on interpersonal theory to characterize the quality and nature of parent- adolescent dyadic interactions using (1) continuous assessment of interpersonal dynamics (CAID) during discussions about alcohol and (2) assessments of parenting style to address the following aims using a longitudinal sample of 250 early adolescent-parent dyads: (1) Characterize parent-child dyadic interactions during discussion of alcohol and other topics using CAID; (2) Test the association of frequency of parent-child alcohol risk discussions and sipping/tasting alcohol with trajectories of adolescent attitudes and beliefs about alcohol (cognitive susceptibility to drinking) and trajectories of alcohol use, and whether characteristics of dyadic interactions and parenting style moderate these associations; (3) Test adolescent alcohol attitudes and beliefs (cognitive susceptibility to drinking) as potential mediators of associations with alcohol use described in aim 2; (4) Test change in parent-adolescent dyadic interactions and parenting style during the transition from early to middle adolescence and the association of these changes with in alcohol use. Addressing these aims will provide much needed clarity on parent alcohol-specific socialization and provide guidance for more effective public health messaging and preventive interventions. Evidence for parental harm reduction efforts to reduce risk for underage drinking is mixed. The proposed research addresses a critical need to clarify parent-adolescent interpersonal dynamics that render prevalent parental harm reduction efforts protective or risk enhancing. Findings from this study will inform public health messages and preventive intervention approaches to consider not just what pa...