This paper recapitulates the aims of the CEFR and highlights three aspects of good practice in exploiting it: firstly, taking as a starting point the real-world language ability that is the aim of all modern language learners; secondly, the exploitation of good descriptors as transparent learning objectives in order to involve and empower the learners; and thirdly, engaging with the "communality" of the CEFR Common Reference Levels in relating assessments to it. The second part of the paper focuses on good practice in such linking of assessments to the CEFR. It outlines the recommended procedures published by the Council of Europe for linking language examinations to the CEFR and the adaptation of those procedures for teacher assessment in language schools that has recently been undertaken by EAQUALS. The paper concludes by discussing certain aspects of criterion-referenced assessment (CR) and standard setting that are relevant to the linking process.