Teacher education all over Europe is increasingly becoming school-based oriented. This implies new roles for those who support student teachers learning in school. This article describes the way four school-based teacher educators fulfill their role as educators of student teachers who learn how to teach while participating in the workplace. Based on theoretical notions derived from the literature on teacher education and workplace learning, the Cognitive Apprenticeship Model was specified and used in a case study as a framework to describe the activity of these school-based teacher educators. They use tools (e.g., apprenticeship assignments) developed within the teacher education institute and rely on their professional knowledge as experienced schoolteachers. This results in student teachers being provided with useful tricks which, however, hardly helps them to interpret and elaborate their experiences from a more conceptual or theoretical perspective. Also the possibilities of the social context of the school as a learning environment are not systematically used. (Contains 2 notes and 1 table.)