What can parents do to prevent antisocial behavior in their youths? This is a central question in parenting research. In the field's literature, answers to this question have been based primarily on theoretical models where parents influence their youths' behaviors, but are not influenced by them. In our research, we have developed theoretical models that, in contrast to this, assume that parents and youths influence each other bidirectionally. Our initial empirical studies show that much of what researchers have seen as parents' actions, are reactions to youths' behaviors. In this project, we will study the youth's active role in the link between parenting behaviors and delinquency development. We will further develop and test a model for reciprocal family processes to help explain how antisocial behavior in youth can be fueled or stopped by parents. The model differs from previous models in its focus on how parents react to youths' behavior at home and in leisure settings. The study also focuses on the emotional reactions of parents and youths as bases for their behavior. The project will test the model with data from a 5-year longitudinal study of all youths aged 10 to 18, and their parents, in one Swedish community.