Unintentional injuries are the leading cause of death and disability for youth under 20, and motor vehicle collisions are the leading cause of death in youth aged 15-19 (World Health Organization, 2010). Research has consistently shown that driver education programs do not result in safer youth driving. Indeed, the biggest predictor of collisions involving youth is parental history of collisions. This dissertation comprised two studies – one to develop a measure of risky driving and one that examined the influence of parents on youth risky driving. Participants (N = 432) for both studies were undergraduate students aged 17 to 22 who had obtained their G2 driver’s licence in the past year. In Study 1, exploratory and confirmatory factor analyses of the new Youth Domains of Risky Driving Scale revealed a four-factor solution consisting of aggressive, substance use, distracted, and moving violation subscales. In Study 2, this new measure was used to evaluate relations between parental modeling of risky driving behaviours, parental teaching about safe driving behaviours, and youth risky driving. Results revealed that parental modeling was generally more predictive of youth risk than parental teaching, for all four subtypes of driving behaviours examined. Youth whose parents modeled risky driving behaviour were more likely be willing to drive in a risky manner, to expect that they would do so in the future, and to report a history of risky driving in the past. Findings from this study highlight the role parents play in the development of youth risky driving. Implications for future interventions targeting parent driving behaviour in the early months of youth licensure are discussed. / Canadian Institutes of Health Research