The Mental Health Model (MHM) of sport performance purports that an inverse relationship exists between psychopathology and sport performance. The model postulates that as an athlete's mental health either worsens or improves performance should fall or rise accordingly, and there is now considerable support for this view. Studies have shown that between 70 and 85% of successful and unsuccessful athletes can be identified using general psychological measures of personality structure and mood state, a level superior to chance but insufficient for the purpose of selecting athletes. Longitudinal MHM research indicates that the mood state responses of athletes exhibit a dose-response relationship with their training load, a finding that has shown potential for reducing the incidence of the staleness syndrome in athletes who undergo intensive physical training. The MHM also has implications for the general care of athletes as support services have traditionally been limited to preventing or treating physical problems. Despite its simple premise and empirical support, the MHM has often been mischaracterised in the sport psychology literature and recently some authors have questioned its validity. This overview will summarise MHM research, including the more recent work involving the model's dynamic features in an effort to resolve disputes surrounding the model.