This brief authored by the Children’s Hospital of Philadelphia’s PolicyLab & Safe Place, explores collaborations—old and new—between child welfare and medical providers. It serves as a resource for states seeking to strengthen these collaborations across the continuum of child welfare services from CPS reporting and investigation to in-home protective services, foster care, and post-reunification services. Part I describes the national policy context related to the promotion of child health and well-being by the child welfare system. Part II examines promising and proven collaborative models related to the reporting and investigation of child maltreatment and the ongoing provision of child welfare services to children and families. Finally, Part III concludes with a discussion about future directions for partnerships between child welfare and health care systems.