This article reviews some of the wide-ranging issues and research surrounding authentic materials and authenticity in foreign language learning. After a brief historical overview and a discussion of some of the definitional ambiguities associated with authenticity, the paper goes on to discuss four important areas of concern: i) the gap between authentic and textbook discourse; ii) the English-as-a-world-language debate; iii) authenticity and motivation; iv) text difficulty and task design and their effects on language acquisition. The article concludes by examining some of the reasons behind resistance to change in curriculum and materials design and possible future directions.