Aggressive, violent and antisocial behaviour in children and adolescents is a growing concern across the globe. Targeting parent-teen relationships is critical in reducing problem behaviour. "Connect" is a manualized ten-week program for parents or alternative caregivers of at-risk teens that focuses on the building blocks of secure attachment: parental sensitivity, cooperation, reflective capacity, and effective dyadic affect regulation. Through didactic and experiential activities, parents develop the competence necessary to identify, understand and respond to the needs of their teen in a manner that provides structure and safety while safeguarding the quality of the parent-teen relationship. In Study 1, twenty parents reported significant increases in perceived parenting satisfaction and efficacy and reductions in adolescents' aggression, antisocial behaviour and other mental health problems following completion of Connect as compared to a waitlist control period. These effects were sustained and additional small effects were noted in decreases in conduct problems, depression and anxiety at a 12-month follow-up. The program was then transported to 17 communities serving 309 parents through standardized training and supervision of group leaders. Study 2 summarizes significant pre- to post-treatment reductions in teen externalizing and internalizing problems; enhanced social functioning; and improvements in affect regulation. Parents also reported significant increases in parenting satisfaction and perceived efficacy and reductions in caregiver burden. (Contains 4 tables.)