Purpose: The paper focuses on current debates about police professionalism. It explores the nature and meaning of what has been termed "old" professionalism, which focuses on the role of the police as "professional crime fighters", and then assesses the extent to which there has been a transition to a "new" professionalism centred on enhanced accountability, legitimacy and evidence-based practice. The paper aims to show how the recent attempt to embed this "new" professionalism within policing in England and Wales is likely to be compromised by the broader political and economic context of police reform. Design/methodology/approach: The paper is based on a review of key contributions to the debates about police professionalism in the USA and the UK. Findings: The paper provides important insights into the way in which there are competing and conflicting meanings attached to police professionalism and argues that claims that there have been significant transitions from one form of professionalism to another need to be treated with caution. The paper also emphasises the uncertain trajectory of the development of police professionalism in England and Wales in the future as a result of the complex interplay between the different elements of the coalition government's police reform programme. Originality/value: The paper demonstrates the multiple meanings of the term "police professionalism" and the challenges that surround developing professional policing.