This volume gives an overview of the impact of the CEFR on teaching and assessment as well as the extensive debate surrounding the framework. It covers the four main areas with which the CEFR is concerned: its role as a common framework, the Common Reference Levels, what the CEFR implies for planning and teaching, and assessment of CEFR levels. A distinction is maintained between practical information and academic discussion. Each chapter is organised into three sections: Essentials, to introduce the relevance of the CEFR to the topic concerned; More detail, to give examples of the implementation of the framework; and Issues, a discursive section with a foucs on misconceptions of the CEFR and how these could be addressed. The conclusion discusses the extent to which the CEFR is generating change, the priorities for curriculum development in the future and how the framework can be further exploited and developed.