A few years ago, David Bayley and Clifford Shearing (1996) argued that at the end of the 20th century we were witnessing a 'watershed' in policing, when transformations were occurring in the practices and sponsorship of policing on a scale unprecedented since the developments that heralded the creation of the 'New Police' in the 19th century. In this special issue of the journal, we and our fellow contributors turn our attention to a somewhat neglected aspect of this 'quiet revolution' in policing (Stenning & Shearing, 1980), namely the nature of the opportunities for, and challenges posed by, the reform of policing in different parts of the world at the beginning of the 21st century. Our attention in this issue is particularly focused on the opportunities, drivers and challenges in reforming public (state-sponsored) police institutions.