The transition from occupational practitioner to vocational educator means moving from the logic of production to the logic of teaching; the purpose of knowledge changes from enhancing production to enhancing learning. This process touches issues of transmitting vocational knowledge from a workplace context to a school context; it has been explored in the literature, but few studies have focused on transmitting vocational knowledge from the perspectives of guiding in a workplace to teaching in a classroom. This article reports a study on the preparation of Norwegian trainee teachers in vocational teacher education. It examines how they talk about the transition from occupational practitioner to vocational educator and identifies important challenges faced by trainee teachers regarding the transition from guiding apprentices to teaching students (i.e., newcomers). The analysis explores how transforming dominant ways of knowing and being as occupational practitioner is crucial to achieving the tasks of a vocational educator.