The goal of this volume is to provide a rich, interdisciplinary foundation of empirical studies describing the discourse of Language Proficiency Interviews (LPIs), focusing on “interactional competence.” The studies not only show how difficult it is to validly assess oral proficiency; they also show that discourse analysis of LPIs—as the editors point out—is very much in its infancy. Most of these studies face research design challenges (e.g., small sample size, sample comparability, coding reliability, or a combination of these), yet they illustrate the potential contributions of various (mostly qualitative) discourse analytic approaches to an understanding and assessment of oral proficiency.