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The present dissertation examines the interplay of dopaminergic genes, parenting, and personality characteristics in the development of externalizing problem behavior in adolescence. We adopted the 'Developmental Systems Theory' as a theoretical framework to investigate this complex interplay (e.g., Bronfenbrenner, 2005; Lerner, Rothbaum, Boulos, & Castellino, 2002). Specifically, we focused on the microsystem that is the interaction between the adolescent and his/her parent(s). The STRATEGIES project (i.e., Studying Transactions in Adolescence: Testing Genes in Interaction With Environments) provided data for the four studies that are part of this dissertation. At Wave 1, the sample consisted of 1116 Flemish adolescents from Grades 7 to 9, 747 mothers, and 645 fathers. During six years, these informants annually reported on parenting practices, adolescent temperament/personality, and externalizing problem behavior. The fourth study additionally included data from the GEM project (i.e., Genes, Environment, and Mood), which consisted of 665 American children from Grade 3, 6, or 9 and one of their parents. The GEM data used in the present dissertation was collected across three waves with a 18-month interval. The first study examined whether parenting practices could be measured in mothers, fathers and adolescents across adolescence using the same questionnaires. Confirmatory factor analyses established (partial) scalar measurement invariance of a five-factor parenting model (i.e., support, proactive control, punitive, non-physical, control, harsh punitive, physical control, and psychological control) by Janssens et al. (2015) across informants (i.e., mothers, fathers, and adolescents) and across developmental periods (i.e., early, middle, and late adolescence). In other words, our findings indicated that this five-factor parenting model can be validly used to represent the perspectives on parenting of mothers, fathers, and adolescents across adolescence. The second study used a person-centered approach to investigate heterogeneity in the five parenting dimensions for mothers and fathers separately. Specifically, longitudinal class growth analyses showed distinguishable longitudinal trajectory classes for each parenting dimension except harsh punitive control. Furthermore, we found these classes to differ regarding externalizing problem behavior (i.e., rule-breaking and aggressive behavior) at age 12. The third study used random intercept cross-lagged panel models to investigate transactional associations between parental control, adolescent personality, and externalizing problem behavior. We found that adolescent personality predicted problem behavior and vice versa. Furthermore, we observed that adolescent personality also predicted parental control and vice versa across early and middle adolescence. The fourth study used two independent samples to examine whether the association between parenting and externalizing problem behavior was mediated by adolescent effortful control, and whether this mediation was moderated by activity of the dopaminergic pathway, represented by a polygenic index score (i.e., DRD2, DRD4, DAT1, and COMT). There was no consistent support for a mediation by adolescent effortful control, but we did observe some evidence of moderation of this mediation model by dopaminergic activity. To conclude, the four studies included in the present dissertation highlight the need of a differentiated approach in the investigation of the development of externalizing problem behavior in adolescence. Such an approach should comprise individual differences, such as personality, temperament, or genetic characteristics, as well as environmental factors, such as parenting practices. The present dissertation provided innovative insights that can aid in the development of theoretical perspectives as well as in the optimization of parenting programs and hopefully inspires future research.