Objectives: This study examined the contribution of motivational climate created by mothers, coaches, and best friends in the explanation of variance of athletes' achievement goals, sport satisfaction and academic performance. Design: Cross-sectional; participants completed self-reports assessing achievement goals in sport, perceptions of goals that are endorsed by mother, coach and best friend, satisfaction in sport and academic achievement. Methods: Participants were 863 current Greek athletes (488 males, 372 females, 3 did not provide gender) aged 14.5 +/-.60 (n = 420) and 11.5 +/-.60 (n = 443). Results: Factor, reliability and correlation analyses supported the psychometric properties of the instruments. All socialization agents had unique contribution to the explained variance of athletes' achievement goals in sport. Mastery goals and perceptions corresponded positively to satisfaction in sport and they had low positive relationship with academic performance. Perceptions of performance approach goals endorsed by significant others had low negative relationship with academic performance and they were unrelated to sport satisfaction. Conclusions: Mastery oriented climates should be established in sport, family, and peer contexts because all social contexts seem responsible for the formation of athletes' achievement goals, emotions, and behaviours.