Self-concepts and sibling relationships were examined in 80 elementary school students: 20 academically gifted children; 20 non-gifted siblings and; 40 control students utilizing the Self Perception Profile for Children (Harter, 1985) and the Sibling Relationships Questionnaire (Furman & Buhrmester, 1985). The study was predominantly exploratory in nature with two main purposes: to assess group differences in self-concepts and global self-esteem and; to explore group differences in perceptions of the sibling relationships. Gifted children were found to report greater Scholastic Competence and Global Self-Esteem compared to all groups, but reported poorer Athletic Competence than did their peers. Non-gifted siblings were found to report poorer Global Self-Esteem than their peers. Gifted children reported greater conflict within their sibling relationships and their non-gifted siblings reported less companionship compared to the control sibling dyads. Findings are discussed within the theoretical framework of labeling theory, Tesser's ( 1980) Self-Esteem Maintenance Model and Social Comparison Theory.