The role of false belief in establishing children's social relationships during the transition to school was examined and compared to other social cognitive constructs. One hundred and fourteen 5-year-olds were recruited during their 1st year of school (Time 1); 106 children were retained 1 year later. False belief, emotion expression recognition, empathy, verbal ability, and peer-rated social preference were measured at both times. False belief at Time 1 had a direct influence on concurrent social preference, over and above the influence of emotion expression recognition and empathy. False belief made no independent contribution to later social preference accounting for stability in social preference. The role of social cognitive development is discussed with respect to how children establish and maintain their position in a peer group.