The purpose of this study was to examine the relations of individual differences in regulation and negative emotionality to 127 third-grade Indonesian children's social skills/low externalizing problem behavior, sociometric status, and shyness. Parents and multiple teachers provided information on children's regulation, negative emotionality, and social functioning; peer sociometric information on liking and social behavior was obtained; and children reported on their self-regulation. In general, children's low socially appropriate behavior/high problem behavior and rejected peer status were related to low dispositional regulation and high negative emotionality (intense emotions and anger), and regulation and negative emotionality (especially teacher rated) sometimes accounted for unique (additive) variance in children's social functioning. Adult-reported shyness was related to low peer nominations of disliked/fights (although shy children were not especially liked), low adult-reported regulation, and (to a lesser degree) low teacher-rated negative emotionality. Findings are compared with work on regulation, negative emotionality, social competence, and shyness in other countries.