This volume distinguishes itself from existing research on materials design, development, and evaluation, and focuses on material mediation in actual processes of teaching and learning, a subject that has been under-researched in the field of applied linguistics and second language education. This edited volume includes diverse perspectives on the roles that materials play in language learner pedagogy. Moving beyond the field of English language teaching, readers will find novel contributions offering a diversity of language teaching contexts, learner populations, and topics in the theory and/or practice of second and foreign language teaching. Chapters explore the ways in which affordances and constraints of classroom materials impact teachers and learners, while at the same time they bring their own (evolving) resources, identities, beliefs, and expertise to modify and adapt the materials to better suit their local language teaching and learning environments. As such, this text is ideal for use as supplemental reading in a wide variety of applied linguistics, second/foreign language education, TESOL, and instructional course design courses.