This chapter summarizes current knowledge about children’s relationships to nature. While nature has always been part of childhood, concern about whether it will retain its traditional roles has risen apace with reduced exposure to it in the West. The chapter first examines Western cultural associations between children and nature, then presents contemporary psychological theories and methods used in this field. Key themes from research include that children are losing access to nature and inhabiting it less; that play in nature is varied and shows developmental patterns; that nature provides both powerful positive and negative emotional experiences; and that children are cognitively equipped to understand the living world. Technological simulations of nature may not provide all that real nature provides. This may include a wide range of physical and psychological benefits that are increasingly recognized.