The history of social work is deeply rooted in helping vulnerable populations improve their well-being, and children have been at the forefront of these efforts since the inception of the profession. Health is long understood to be critical to children’s well-being. Social workers who are skilled in integrating different systems can play pivotal roles in engineering new and improving existing health-care infrastructures and can act as advocates for fusing health-service systems with other social infrastructures to optimize outcomes for children. This entry reviews trends in children’s health throughout the world, particularly in the United States. It describes the dramatic improvements in reducing infant mortality, child mortality and morbidity from many infectious diseases as well as accidental and environmental causes, and the unequal progress in realizing children’s health. The challenges that lie ahead that pose risks to children’s health are discussed, including the health inequities created among and within countries by social, economic, and political factors. An argument for a comprehensive, integrated, evidence-based, and cross-disciplinary approach to improve children’s future health is presented.