Exploring Iranian ESP teachers’ language-related critical incidents.

English for specific purposes (ESP) practitioners who are content experts experience different types of critical incidents (CIs), which are unplanned and unexpected events that happen during a lesson or outside of the classroom, leading to insights about teaching and learning. Although CIs can influence the success or failure of ESP courses and impact on ESP practitioners’ professional lives significantly, they have received only limited attention in the ESP literature. This study investigates language-related CIs experienced by ESP instructors who are content experts. Twenty-seven CIs were identified via narrative frames (n = 17) and interviews with Iranian ESP practitioners (n = 10). Of them, the ten language-related CIs were analyzed in terms of their nature, the strategies and tactics that the ESP practitioners utilized to tackle them, and the lessons that they learned from them. These CIs centered on difficulty in pronunciation, grammar, teaching reading and writing, language testing, and research on academic genres. In their response to the CIs, the ESP instructors deployed three types of coping strategy: admitting ignorance, avoidance, and risk-taking. They utilized different tactics to manage their CIs and reported different lessons learned. The results of this study have important implications because they shed light on the real difficulties encountered by ESP practitioners who are content experts and highlight the need for ESP teacher training programs.