The main perspective taken in this paper is that peer relationships in childhood provide more than incidental social experiences and constitute social contexts beyond those in the family. In the context of peer relationships, children's development continues to progress as children expand their experiences and increase their knowledge. Three major directions in the research are examined: the first section of this chapter provides a review of the major theoretical perspectives and empirical research on children's peer relationships in child development. In the second section, the findings of this research are related to questions that educators and parents may ask as they observe peer interaction in the classroom, home, or neighborhood. Throughout these two sections the implications for children's social experience in the school and at home are discussed and future research directions are proposed. In the last section, the role of adults in the development of children's peer relationships is reviewed according to available evidence, and methods for supporting and instructing children in peer relationship development are discussed. Various types of curriculum activity are then examined for their potential influence on peer relationships, especially those relationships between children of different ages, races, sexes, and abilities. (Author/DB)