Social Interaction and L2 Classroom Discourse is a meticulous and well-written book that provides rigorous empirical analysis of important moments in the L2 English classroom, including the co-construction of understanding, interactional troubles and their resolution, and the microgenesis of L2 (classroom) interactional competence. It is an important contribution to the field of applied linguistics because it consolidates ideas in conversation analysis in order to make recommendations for L2 pedagogy that are both well-warranted, deriving as they do from a robust empirical record, and exceptionally practical.