This chapter reviews the current state of the literature on children and adolescents' dyadic peer relationships. Particular emphasis is placed on children and adolescents' same‐sex friendships and romantic relationships, but research on other‐sex friendships, antipathies, passionate friendships, and sexual relationships are covered as well. The chapter uses a unified relational perspective, which has four key points. First, friendships and romantic relationships need to be studied as relationships. They are dyadic phenomena with a history. Second, children and adolescents' friendships, romantic relationships, and other peer relationships all share common features. They have been studied as separate phenomena and typically by different investigators, but the field would benefit by simultaneously considering all of these types of relationships. Third, any particular relationship is embedded in a network of dyadic relationships. Finally, dyadic peer relationships cannot be understood without incorporating the contexts in which they occur, such as the general peer group, family, and culture.
Using this unified relational perspective, the chapter reviews research on the development of dyadic relationships, the role of the self and partner and gender. The chapter then discusses the associations with family relationships, the peer group, media, and the cultural context in which they are embedded. The links between relationships and adjustment are also covered. The chapter also outlines a number of definitional, conceptual, methodological, and analytical issues that need to be addressed in future research, and identifies a number of understudied topics. It concludes by discussing the merits of the unified relational perspective.