This entry addresses the possibilities of being a teacher by examining the concept of teacher identity from the philosophical perspectives of life-world phenomenology or, more specifically, from the perspective offered by Martin Heidegger. As the discourses on teacher identity are imbued with conceptions of learning, as well as teaching, which is viewed as instrumental, linear, quantifiable, and competence-based, the professional identity of teacher runs the risk of being addressed mainly as an epistemological project of efficacy.