This theoretical-review paper presents the construct of interactional identities as part of the study of classroom interaction in English language teaching education. The paper defines interactional identities from social studies and in the field of English language teaching. By listing studies on the matter, the relationship of this construct with classroom interaction is presented from global and local perspectives. Three reasons for studying interactional identities in the ELT field are discussed in the final part of the paper whose conclusions invite to incorporate this construct into de study of what teachers are and do for language learning and use in classroom interaction in English language teaching education.