Level C2, whilst it has been termed ‘Mastery’, is not intended to imply native-speaker or near native-speaker competence. What is intended is to characterise the degree of precision, appropriateness and ease with the language which typifies the speech of those who have been highly successful learners. Descriptors calibrated here include: convey finer shades of meaning precisely by using, with reasonable accuracy, a wide range of modification devices; has a good command of idiomatic expressions and colloquialisms with awareness of connotative level of meaning; backtrack and restructure around a difficulty so smoothly the interlocutor is hardly aware of it.