Assessed preschoolers' patterns of emotional expressiveness, emotion regulation, and emotion knowledge. Used latent variable modeling to identify their contributions to social competence, evidenced by sociometric liability and teacher ratings. Found that emotional competence assessed at 3 to 4 years of age contributed to both concurrent and kindergarten social competence. Concluded that early in the preschool period, contributions of emotional competence to social competence have long-term implications. (Author/KB)