Coaching effectiveness: the coach-athlete relationship at its heart

•The essence of coaching effectiveness has yet to be agreed and captured.•Proliferation of coaching conceptualisations limits its systematic study.•Coaching effectiveness hinges on quality coach-athlete relationships.•A solution-focused, system model offers new possibilities for research and practice.

Coaching has been often viewed as a context within which coaches operate to largely bring about changes in athlete's performance and wellbeing. One key factor to successful outcomes in coaching is the quality of the relationship between coaches and athletes. In this article, I propose that the coach-athlete relationship is at the heart of coaching. Moreover, the aim is to describe and explain how the quality of the relationship coaches and athletes develop and maintain over the course of their sporting partnership alongside coaches and athletes' knowledge and outcomes, form a system that is capable of defining coaching effectiveness and success.