Integrated pediatric behavioral health is the practice of colocating and integrating behavioral health providers into the primary care pediatric setting. Pediatric primary care, a nearly universally accessed venue by children, represents a promising path to take behavioral health prevention and treatment to scale. However, child psychologists wishing to practice in such a setting face limited training opportunities and few options to learn the evidence-based interventions and skills needed to excel in these settings. We describe our pediatric life span–integrated behavioral health model, including Healthy Steps for children and their families starting at birth, and a child and adolescent model for children ages 5 and up. We review the need to improve the evidence base in pediatric integrated behavioral health and present our modularized intervention protocols. We review staffing ratios, workforce development, and other programmatic design elements. We present our feasibility findings and suggest that a pediatric life-span model of integrated care may be the best mechanism for taking behavioral health prevention and treatment to scale.