Over the last two decades the public sector has been the target of significant change driven primarily by advocates of public choice theory who argue that the public sector is too large and inefficient. Changes, grouped under the banner of New Public Management, have therefore been aimed at achieving greater financial accountability through the adoption of private sector management techniques and the opening up to competition of monopolistic government supplied services. Recent reappraisals of these changes have suggested that they have failed to adequately address issues of social justice. It has therefore been proposed that public sector organisations now need to consider more egalitarian methods of service delivery through greater public consultation and involvement in decision making processes. Studies over the last 20 years in the public sector have tended to concentrate on change aimed at achieving New Public Management outcomes. This study adds to theory of culture and culture change in public sector organisations through exploring a change purposefully enacted to enable an organisation to meet both economic rationalist and egalitarian objectives. The primary aim of this thesis is to explore a planned process of cultural change within a technically oriented, public sector organisation to determine the processes used to undertake such change, the resulting outcomes and why these outcomes occur. A case study was used to investigate these areas. The study was longitudinal and used a combination of methods including focus groups, interviews, non-participant observation and document analysis. Historical data was first obtained to form a base from which to examine the process of planned change over a two year period. This method allowed consideration of the impact of contextual changes on the planned process that resulted in some unintended consequences in regard to how change was being driven. The findings conclude that models of planned change that include mechanisms through which diversity is encouraged may provide arenas through which conflict can act as a positive dynamic for change. The outcome of the planned change evidences how a purposefully created hybrid organisational form may be capable of addressing the sometimes conflicting goals of economic rationalism and citizenship participation.