Introduction Since the first professional doctorates were introduced in the UK in 1992 (Bourner, Bowden and Laing, 2001) there has been a considerable growth in the number and range of programmes being offered. The most recent national survey undertaken in 2005 by the UK Council for Graduate Education (UKCGE) identified 192 programmes offered across a broad field of disciplinary areas (Powell and Long, 2005). Whilst programmes in areas such as education, engineering and business administration have become well established, it is only in the last few years that programmes targeted specifically at the Criminal Justice Sector have begun to emerge. In this article, we outline the history, structure and characteristics of the professional doctorate and position the qualification in the wider context of education and training within the Criminal Justice Sector. We offer a comparison of the professional doctorate programmes that are currently available and consider how different structures, curricula and modes of assessment may reflect different conceptions of what constitutes valid knowledge. We conclude that the professional doctorate provides an exciting opportunity for criminal justice professionals to receive a higher level award that provides recognition of their contribution both to academic knowledge and to professional practice. However, the nature of the award also has some implications for the relationship between higher education and the Criminal Justice Sector, which may require further consideration.