Abstract

_ Professional development is a critical concept in the literature on teaching and teacher education. However, in this literature, continuous growth (learning)—e.g., improve teaching strategies, elaborate a variety of activities or integrate new technologies into their practice—is not distinguished from (crisis-like) change to qualitatively different forms of experience—e.g., engage students in learning, implement student-centered practices, consider students' individual needs and further learning. Based on a case study of the change a Brazilian teacher experienced over the course of an 8-year period, we develop an approach based on ideas of the Russian psychologist L. S. Vygotsky that not only theorizes a distinction between learning and development but also the articulation between the two processes whereby continuous change turns into discontinuous change. _.