The Triple P Positive Parenting Program is a multilevel parenting program to prevent and offer treatment for severe behavioral, emotional, and developmental problems in children. The aim of this meta-analysis is to assess the effectiveness of Triple P Level 4 interventions in the management of behavioral problems in children by pooling the evidence from relevant literature that included Level 4 Triple P interventions. Level 4 intervention is indicated if the child has multiple behavior problems in a variety of settings and there are clear deficits in parenting skills. Results indicate that Level 4 of Triple P interventions reduced disruptive behaviors in children. These improvements were maintained well over time, with further improvements in long-term follow-up. These effects support the widespread adoption and implementation of Triple P that is taking place in an increasing number of countries in quite diverse cultural contexts around the world. (Contains 3 tables.)