A controlling or pressuring coaching style can best be avoided, as it comes with a number of costs, including athlete ill-being, reduced sport enjoyment and higher drop-out rates. To reduce youth coaches’ reliance on a controlling style, it is important to understand its underlying sources. In this project, it will be investigated whether the extent to which coaches adopt a controlling coaching style depends on their tendency to let their self-esteem depend on the successes and failures of their athletes, in other words, on their athlete-invested contingent self-esteem. In a cumulative series experimental and longitudinal studies, the role of (a) a pressure-exerting sports climate and (b) poor athlete performances in the prediction of such fragile self-esteem is examined.