How do you know if you’re practising CLIL?

Perhaps due to its relatively recent birth as an approach with a label, CLIL shelters a broad range of practice under its pedagogic roof. But if it is to be taken seriously as an approach, and then adopted by the world of pedagogy, it needs to have identifiable limits. We need to be able to say what it is, but also what it isn’t. In what ways does CLIL manifest itself in terms of curricular types, and perhaps more simply – how do you know if you’re ‘CLIL-ing’, to quote a new verb?