“…A Lesson Study cycle includes the development of a lesson plan, the implementation of the lesson plan in a classroom by one of the group members, while other teachers observe, and a postlesson discussion to analyse its impact on students' learning, in which the group may decide to plan an improved version of the lesson, and the cycle begins again (Chen & Yang, 2013;Fernandez & Yoshida, 2004;Lewis, 2002;Lewis et al, 2009). In some Lesson Study scenarios, and particularly so in Japan, actors operate in an environment where roles are clearly defined (as discussed in the Theme C paper by Clivaz & Daina, 2020; see also Clivaz & Takahashi, 2018, and Sect. 4.5.3 below).…”