The current study was designed to address two major purposes. The first goal was to investigate the joint influence of children's sociometric status and sex on their conflict behavior, and the second goal was to explore the similarities and differences in children's conflict behavior across two contexts, specifically conflicts arising during interactions with mothers and with peers. Forty-two first-graders were videotaped playing with their mothers and then with an unfamiliar pecr partner. Conflict behavior occurring in the motherchild context was quite different from that occurring between children, reflecting the contrast between the vertical and horizontal nature of these relationships. Most striking were the large number of sociometric status and sex differences in conflict behavior found across both contexts. Further, it appears that effective conflict behavior may differ for boys and girls. Implications for future research are discussed.