This article focuses on how mindfulness training (MT) programs for teachers, by cultivating mindfulness and its application to stress management and the social-emotional demands of teaching, represent emerging forms of teacher professional development (PD) aimed at improving teaching in public schools. MT is hypothesized to promote teachers' “habits of mind,” and thereby their occupational health, well-being, and capacities to create and sustain both supportive relationships with students and classroom climates conducive to student engagement and learning. After defining mindfulness and its potential applications in teacher education and PD, this article discusses emerging MT programs for teachers, a logic model outlining potential MT program effects in educational settings, and directions for future research.