Knowledge that teachers bring to the teaching context is one of the key factors in discussions about mathematics teaching. This study aimed to explore in-service primary teachers' knowledge of fraction division using division tasks. The first phase of the study examined fifty-one primary in-service teachers' written responses to division items. This sample of teachers represented seven different countries in the South Pacific region. The second phase of the study used focus group discussions with a smaller sample of teachers, to provide an in-depth analysis of teachers' knowledge of fraction division. The results from phase one indicated that the in-service teachers lacked a sound conceptual understanding of fraction division. In the second phase of the study, however, two out of the five teachers showed signs of developing a conceptual understanding of fraction division. This has implications for teacher professional learning and development.