A wealth of research demonstrates the importance of early parent-child interactions on children's social functioning. However, less is known about the interrelations between child and parent characteristics and parent-child interactions in early childhood. Moreover, few studies have broadly examined the longitudinal relations between these constructs and social competence. This study is an examination of the relations between parent responsiveness, negativity, and emotional supportiveness, attachment security, and child temperament, and their impact on children's social competence from infancy to kindergarten entry. The sample was derived from the Early Childhood Longitudinal Study--Birth Cohort and included 6850 parent-child dyads. Observational and rating scale data were used. The proposed model was nearly fully supported by path analysis, and it provides insight into the complex relations between early parenting behaviors, child characteristics, and parent-child interactions in the development of social competence.