Over recent years Performance Indicators and Performance Management have become considerably more prominent within the United Kingdom (UK) to the point where they have become the Government's primary tool for managing the Public Sector. Many positive benefits are claimed for this development and much has been made of the improved service that appears to have resulted. However there have also been dissenting voices claiming that many of the claimed benefits have been achieved at the expense of other, often unplanned, reductions in quality. The main aim of this research was to study and assesses of the effectiveness of the performance management systems employed within the United Kingdom Public Sector. However addressing this key question also raised the supplementary issue of the potential dysfunctional consequences that may be experienced from implementing and using these systems. To fully consider this issue it has been considered from two perspectives. The external perspective took into account the wider environmental context in which the organisation is operating whereas the internal perspective considered the issues from the view or the organisation itself, its management and the staff operating within the organisation. From the external view the key issue considered was whether there had been an improvement in public sector performance since the introduction of performance management. There is a wide range of published secondary data which has been utilised for initial analysis and for cross referencing with the primary data gathered directly from the organisations using the main data collection instrument. The internal view attempted to ascertain what the elements of effective performance management are with reference to several of the key reported organisational issues and managerial tools that are available. When both the internal and external perspectives were taken in to consideration the research addressed the overall use of Performance Management techniques within the United Kingdom public sector and considered if they have had an overall beneficial impact. The effectiveness and efficiency of these techniques along with the key influencing factors are considered along with any legal implications. Within this research project both quantitative and qualitative methodologies are employed in order to provide as broad an analysis of the situation as possible. Qualitative methodologies employed include a literature review, in order to establish the theoretical background for the introduction of public sector performance management, and interviews with the key decision makers, to establish the views on the choice of indicators and implementation procedures selected. Quantitative methodologies are the key primary data collection tool and are based around a survey of the users of the performance management systems to ascertain their views as to the usefulness and effectiveness of the systems and the associated procedures. The study targeted public sector organisation within the UK and the unit of analysis was the individual public sector employee, in total 1111 employees from 124 public sector organisations participated in the study. The research suggests that whilst there have been improvements in public services that can be related to the performance management systems that have been employed these improvements have not come without significant costs, financial and otherwise.