The ability to use vague language ("bags of time", "doing stuff", "sort of thing", "and all that") is an aspect of communicative competence of considerable social importance. Vague Language Explored examines the function of vague language in context. It spans genre analysis, critical discourse analysis, psycholinguistics and cross-cultural sociolinguistics, in a variety of world cultures - examining applications in professional, educational, and social contexts. In EFL applications it asks questions such as "What should learners be taught to understand and use, and why?" and suggests directions for future research.