Neuro-linguistic programming (NLP) is an approach to language teaching which is claimed to help achieve excellence in learner performance. Yet there is little evidence of the impact that NLP techniques in teachers' discourse can have on learners. The article draws on workshops with teachers where classroom simulations were used to raise teachers' awareness of the role that NLP can play in teachers' verbal interaction with their students. The workshops enhanced teachers' awareness of the fact that by creating or ruining teacher-learner congruence their classroom discourse can lead learners to success or failure.