Friendship is a developmentally significant relationship in childhood and adolescence that contributes to socioemotional, social-cognitive, and psychological development and well-being. It is a dyadic relationship based on mutual affection, with both friends thinking of each other as friends. Despite this definitional understanding of the dyadic nature of friendship, it is common to study friendships individually, for example, by investigating how one child's perception of the quality of a friendship is associated with that child's psychological functioning. Although this research approach yields important information about friendships and their effects on youth, we suggest that putting the dyad back into friendship research, by conceptualizing the dyad as the unit of analysis or by including characteristics or perceptions of both members of the dyad in analyses, will generate valuable new knowledge about friendships and their developmental significance. We focus on three key areas of study about children's and adolescents' friendships that would benefit from a dyadic perspective: (a) features and processes in friendships, (b) temporal and contextual approaches to the study of friendship, and (c) friendship tasks and social-cognitive perspectives on intervention.