The articles in this special issue contribute to understanding the interactional grounding of language learning by scrutinizing how patterns of language use emerge and get routinized as dynamic resources for accomplishing actions in co-constructed interaction. Their findings problematize how grammar is represented in second language (L2) teaching materials and have important implications for future research and language pedagogy. In this commentary, we address some of these implications focusing on two questions: (a) how the studies change the conceptualization of grammar as an object of L2 learning and teaching, and (b) how the insights of this research can inform language teaching.