This paper explores the introduction of New Public Management (NPM) techniques within the UK police service since the late 1990s, and in particular, the impact upon the role of the first line manager: the police sergeant. It draws upon qualitative data collected within 'City Police Service' by means of in-depth interviews with role sets of police sergeants, constables, inspectors and members of the senior management team in two police divisions. After evaluating a number of NPM precepts in the light of the findings, the paper makes a number of conclusions relating to the role of police sergeants. These echo the findings of other research on changes in managerial roles, including a shift towards more strategic responsibilities, but with a significant intensification of work, tighter control and scrutiny through organizational performance management systems, and less daily contact with their police constables. As elsewhere in the public sector, a shift towards becoming a 'practitioner manager' was apparent, but with respect to police sergeants the effect was to limit their ability to provide leadership and support for their constables, and to encourage a greater reliance upon peer group networks and on the constables they supervised.