This chapter focuses on the development of interactional competence from a Vygotskian perspective. It is argued that interactional competence is a situated activity in which speakers draw on their historically rooted understanding of contextually appropriate communicative resources in order to create a shared conceptual space for interaction. One dimension of this shared conceptual space is the degree of social distance and power, as created through the use of such register features as second-person pronouns in European languages (e.g., French tu and vous). To show how this aspect of register, and therefore interactional competence, can develop in pedagogical context, I draw on recent studies of concept-based pragmatics instruction. Pedagogical implications and future research directions are presented in concluding.