Two assumptions that underlie much research in early childhood music education are that music is a social endeavor and musical participation is beneficial to children's overall social development. As members of cultural and social groups, young children engage with music in a multitude of ways and with different companions. This article examines young children's musical engagement from a social perspective, integrating research from a wide range of fields and theoretical orientations. The first section brings forward a discussion on the nature of social interactions with an emphasis on three building blocks of social cognition and their relationships to musical experiences of young children. Studies on rhythmic entrainment, social identity in childhood, musical play, and the effects of formal music education on children's social development are discussed in the next sections, along with some of the caveats of current theorizing. Implications for future research and practice in music education are woven throughout the text.