Holding an athletic identity may promote an enduring commitment to sport or physical activity across the lifespan. We examined athletic identity in relation to other processes prominent in sport participation; namely sport orientations wherein individuals evaluate their competence and their success. Win, goal, and competitive orientations were examined as possible mediators of the relation between sport participation and athletic identity in girls and boys separately. The sample included 73 girls and 90 boys (M = 13.8 years, SD = 1.88) attending summer sports camps. Participants completed a questionnaire which investigated sport participation, athletic identity, and sport orientations. Athletic identity was assessed using the Athletic Identity Measurement Scale (AIMS; Brewer et al., 1993). Measures of sport orientation were based on the Sport Orientation Questionnaire (Gill & Deeter, 1988). To test for mediation, regression analyses were conducted based on Kenny's (2003; Baron & Kenny, 1986) recommendations. In addition, a test of the mediational effect was conducted using the z-value provided in the Goodman (II) test (Goodman, 1960). Results indicated that for girls win orientation was a mediator of sport participation and athletic identity (z = 1.96, p < .05); for boys, goal orientation was a mediator (z = 2.13, p < .03). The mediational influence of having a win orientation on girls’ athletic identity may be related to cultural views of sport participation. Because the role of athlete is not associated with the traditional female gender role, the standards that girls use to define themselves as athletes may be different than for boys. Winning may provide girls with concrete affirmation of their physical abilities as well as public status and recognition. The mediational influence of having a goal orientation on boys’ athletic identity may be related to the instrumental focus that is common in boys’ gender-typed activities. From early childhood, boys tend to be more likely than girls to engage in solitary pursuits such as construction play (see Leaper, 1994). The instrumental focus of these activities may be reinforced in sport where practice and hard work are encouraged and the emphasis is on oneself. In summary, our research suggests that adolescent girls and boys may construct athletic identities differently. In particular, we found that different sport orientations mediate the association between sport participation and athletic identity for girls and boys. Keyword(s): gender issues, high school issues, youth sports