Health, nutrition and physical activity are fundamental to children’s development and well-being, and the early lifestyle habits that children acquire lay the foundation for a lifetime of behaviors that promote or undermine their health and well-being. This chapter overviews current issues in these domains of children’s functioning, and explores the role that parents play in supporting children’s health, nutrition, and physical activity. Parenting is embedded within a broader socioecological framework, and this chapter focuses on theories and empirical evidence which attempt to explain how parents influence children’s outcomes in these domains. This is an evolving area of research with significant implications for the health and well-being of not only children but also the adults they will become.