The direct links between mothers’ and fathers’ personality, parenting behaviors, and adolescent behavior problems were examined, as well as the potential mediating influence of parenting behaviors on links between parental personality and child adjustment. This longitudinal, prospective study included 111 adolescents and their mothers and fathers. Results based on mothers’, fathers’, and adolescents’ reports of behavioral adjustment concurred: adolescents with more conscientious mothers had fewer externalizing behaviors. Additionally, mothers and fathers who rated themselves as more conscientious reported greater ease in setting limits for their adolescents. For both parents, parenting behaviors related to their adolescent’s externalizing behavior problems. Maternal limit setting mediated the direct relation between maternal personality and adolescent adjustment. These findings highlight parental conscientiousness as a personality trait related to parents’ ease in setting limits in their parental role and corroborate the significant relation between limit setting as a parental behavior potentially facilitating adolescents’ behavioral adjustment.