Corpus techniques at work in the ELT classroom

The present paper has a theoretical and a practical aim: firts of all, it discusses the place of corpus techniques used for language exploration and learning in Second Language Acquisition (SLA) and English Language Teaching (ELT) theories; secondly, the practical aim consists of a demonstration of how corpus-driven techniques pinpoint the fundamental role of idiomaticity in language use and how this should be focused upon in the language classroom if language teaching aims to promote learners' effective command of the target language and competent communicative ability.