Teachers' authenticity is a topic of emerging interest in the field of education. This paper systematically reviews existing qualitative research on the subject of teachers' authenticity from the perspective of teachers and students. The findings from 12 studies are subject to a metasynthesis. Results show that the authentic teacher is conceptualised as congruent, caring, open to encounters and critically conscious. The conditions that foster teacher authenticity are social belonging, self-organising school systems, intentional critical consciousnesses and intrinsic (caring) motivation. These are contrasted with the perceived inhibitors of authenticity: alienation; systemic control; and a Kafkaesque approach. Implications and recommendations for further research are proposed.