Mercer (2018) makes a compelling argument for the urgent need to further research teacher psychology, focussing on language teachers. While there has been considerable research on language learner psychology and with considerable focus on individual differences (IDs), there have been comparatively few studies into language teacher psychology. Mercer (2018, p. 506) highlights that teachers are among the most important stake holders in the language learning and teaching process. Therefore, it is essential to understand the psychology of both learners and teachers to achieve the best learning outcomes.