This paper is concerned with the craft knowledge of teaching, that is, the professional knowledge gained by experience which teachers use everyday in their classrooms but which is rarely articulated in any conscious manner. The notion of craft knowledge emerged as part of a wider study, which used life-history interviews to investigate the identity and work practices of ten learning support teachers (LSTs) in primary schools in the east coast of Ireland. Craft knowledge was just one of the themes distilled from their accounts which offer a glimpse into the lives and perspectives of these LSTs. Those who are privileged enough to observe successful teachers recognise their craft-knowledge at work even though they often struggle to define it coherently. It is suggested in this paper that even though it is at the heart of effective teaching, teachers' craft-knowledge has been undervalued and under-researched. In the current educational climate of change, with its emphasis on teachers' continuous professional development, there is much to be gained from studying the craft knowledge of teaching, particularly from the perspective of the teacher.