Interaction and grammar is a valuable addition to the Cambridge “Studies in Interactional Sociolinguistics” series. The book is a collection of papers that all, in one way or another, and within the frameworks of linguistic anthropology, functional grammar, or conversation analysis, investigate the interface, or rather the essential interrelatedness, of language and real-time social interaction. The value of the book for the L2 researcher or practitioner is perhaps not direct; however, because much of L2 research focuses on interaction and draws its data from naturally occurring discourse, the indirect contribution is notable. In particular, the chapter by Fox, Hayashi, and Jasperson beautifully underscores those typological differences between English and Japanese that lead to different interactional strategies—an issue of direct relevance to L2 studies.