Against a backdrop of rapid global transformations, the ever-increasing migration of people across nation-state borders and a wide array of language practices, applied linguists, and language and intercultural communication researchers in particular, often include identity as a key construct in their work. Most adopt a broadly poststructuralist approach, drawing on the work of social theorists working in a wide range of areas such as cultural studies, gender studies and critical theory. However, the complexity of these sources poses challenges for these researchers and the aim of this paper is to discuss one such challenge: the theoretical tension between structure and agency, a tension often mentioned but seldom explored in depth. First, I examine how identity, structure and agency might be defined. Second, I then embark on a selective discussion of how structure and agency have been framed by key thinkers in the social sciences, ranging from Karl Marx to Ulrich Beck, Anthony Giddens and Pierre Bourdieu. Third, I examine the work of Margaret Archer, who has explicitly and deliberately taken on the dilemma of structure and agency and developed a suggestive way of thinking about the interrelationship between the two. Finally, I end with a consideration of how my fellow contributors to this special issue of "Language and Intercultural Communication" have incorporated structure and agency into their papers, followed by suggestions of how language and intercultural communication researchers interested in problematising structure and agency might proceed in the future. (Contains 2 tables and 1 figure.)