This paper looks at the employment of metalanguage by advanced English L2 users engaged in Dictogloss, a form-focused collaborative writing task, and compares it with that in an earlier study of intermediate learners. First, three commonly employed types of metalinguistic terms are recognised, listed and compared with those reported in a study of students engaged in meaning-focused interactions. Second, grammatical and lexical Language Related Episodes (LREs) which contain metalanguage are categorised, and their frequency of occurrence is compared. The advanced learners are shown to use metalanguage much more often than their intermediate counterparts, particularly in lexical episodes. Third, the role of metalanguage in enabling learners to attend to form is investigated. The examination of transcripts of learner interactions provides evidence that metalanguage can play a facilitative role in focusing attention and deciding which form to use. Learners focus on some language points just once during a Dictogloss task (continuous LREs) but some of their other decisions on choice of form are reviewed on at least one occasion (discontinuous LREs). Advanced learners are shown to be more likely to re-engage with a form when using metalanguage than when not doing so.