The ABCD initiative aims to strengthen states' capacity to deliver preventative care and early identification services to support young children's healthy development. The goal is to identify, test, and spread policy and system changes that create efficient linkages between pediatric primary care providers and other child and family service providers. The 3-year initiative involves a learning collaborative of 5 states testing interventions at the primary care practice, community, and systems levels to improve connections between healthcare and services like early intervention, education, mental health, and family support programs.