With the advent of Artificial Intelligence and its rapid introduction into educational settings, the roles of teacher and instructional structures are now facing enormous challenges. In the instruction of English as a Foreign Language (EFL) writing in Japan, the national Course of Study encourages introduction of a process-oriented approach in the classroom. However, many teachers at secondary level are unsure as to how they can effectively incorporate teacher and peer feedback, which are key components of this approach. Furthermore, a number of advanced AI tools that have the potential to function as mediators of teacher feedback/assessment have been developed. Some researchers highlight the beneficial usage of AI tools in education, while others issue warnings against their use. The greatest fear seems to be that AI might eventually replace human teachers. This chapter reviews the literature of teacher and peer feedback, which is “regarded as central to writing development” [Hyland (Teaching and researching writing, 2009, p. 245)]. It emphasizes the significant roles of teacher and peer feedback by presenting empirical research. At the end, a number of suggestions are made regarding how teacher and peer feedback can be best utilized in EFL classrooms in ways that do not interfere with the use of AI tools.