This article surveys recent work on content-and-language integrated learning (CLIL). Related to both content-based instruction and immersion education by virtue of its dual focus on language and content, CLIL is here understood as an educational model for contexts where the classroom provides the only site for learners' interaction in the target language. That is, CLIL is about either foreign languages or lingua francas. The discussion foregrounds a prototypical CLIL context (Europe) but also refers to work done elsewhere. The first part of the discussion focuses on policy issues, describing how CLIL practice operates in a tension between grassroots decisions and higher order policymaking, an area where European multi-and plurilingual policies and the strong impact of English as a lingua franca play a particularly interesting role. The latter is, of course, of definite relevance also in other parts of the world. The second part of the article synthesizes research on learning outcomes in CLIL. Here, the absence of standardized content testing means that the main focus is on language-learning outcomes. The third section deals with classroom-based CLIL research and participants' use of their language resources for learning and teaching, including such diverse perspectives as discourse pragmatics, speech acts, academic language functions, and genre. The final part of the article discusses theoretical underpinnings of CLIL, delineating their current state of elaboration as applied linguistic research in the area is gaining momentum.