What do classroom assistants do? How are they deployed and how do teachers manage and liaise with them? These are some of the questions, which an evaluation of the Classroom Assistant Initiative in Scotland sought to answer. In this article the authors, first, set the context by describing the growing use of non-teaching staff. Second, they show how headteachers and class teachers actually deployed and managed assistants in ways that impacted on teachers’ time and classroom organisation. Finally by way of a conclusion, issues related to the use of classroom assistants are highlighted. In particular, despite the generally positive response to the Initiative, many schools were finding it difficult to make sufficient time available for teachers and classroom assistants to plan their work together. Without planning and liaison time, the authors suggest that the benefits from an ‘extra pair of hands’ in the classroom will be limited.