Few jobs come without irritations, and foreign language instruction comes with its own particular set of frustrations which, when accumulated, can lead to stress and eventual burnout for teachers. One mechanism for reducing such frustrations is that of emotion regulation, the cognitive and behavioral strategies individuals employ to manage the emotions they experience or display. To date, no known studies have reported specifically on the in-class frustration experienced by language teachers, or on how teachers regulate their feelings of frustration. Herein, the authors discuss the experiences of seven EFL teachers at a university in Japan obtained through a series of semistructured interviews, classroom observations and corresponding stimulated-recall sessions. The authors discuss four salient thematic frustrations: student apathy, classroom silence, misbehavior in the context of relational strain, and working conditions. The results reveal that participants applied contextually-dependent emotion regulation behaviors, the success of which was often contingent on the participants’ levels of confidence and control over the stressors. Thus, participants showed more success in managing pervasive low-level stressors such as apathy and silence, and more support would be welcome to aid them to manage more debilitating stressors such as student misbehavior. The authors offer suggestions for teachers, trainers and institutions on reducing frustration