Children's health and development outcomes follow a social gradient: the further up the socioeconomic spectrum, the better the outcomes. Based upon a review of multiple forms of evidence, and with a specific focus upon Australia, this article investigates the causes of these socially produced inequities, their impact upon health and development during the early years and what works to reduce these inequities. Using VicHealth's Fair Foundations framework, we report upon child health inequity at three different levels: the socioeconomic, political and cultural level; daily living conditions; the individual health-related behaviours. Although intensive interventions may improve the absolute conditions of significantly disadvantaged children and families, interventions that have been shown to effectively reduce the gap between the best and worst off families are rare. Numerous interventions have been shown to improve some aspect of prenatal, postnatal, family, physical and social environments for young children; however, sustainable or direct effects are difficult to achieve. Inequitable access to services has the potential to maintain or increase inequities during the early years, because those families most in need of services are typically least able to access them. Reducing inequities during early childhood requires a multi-level, multi-faceted response that incorporates: approaches to governance and decision-making; policies that improve access to quality services and facilitate secure, stable, flexible workplaces for parents; service systems that reflect the characteristics of proportionate universalism, function collaboratively, and deliver evidence-based programs in inclusive environments; strong, supportive communities; and information and timely assistance for parents so they feel supported and confident.