Participation is a major outcome area for physical therapists serving young children with disabilities. Contemporary models of disability such as the International Classification of Function, developmental theories such as the system perspective, and evidence-based early childhood practices recognize the interdependence of developmental domains, and suggest that change in 1 area of development influences change in another. Physical therapy provided in naturally occurring activities and routines, considered the preferred service delivery method, promotes participation of young children with disabilities. Research indicates that: (1) children develop skills, become independent, and form relationships through participation; and (2) with developing skills, children can increasingly participate. The purpose of this Perspective article is to synthesize the literature examining the relationship between motor skill development and the social interaction dimension of participation in young children. Current research examining the influence of motor skill development on social interactions in children with autism spectrum disorder will be discussed, exemplifying the interdependence of developmental domains. Implications for physical therapist practice and recommendations for future research are provided.