This thesis explores the tensions between policy and practice in community participation in Health Improvement Programmes (HImPs). The HImP is used as a vehicle through which partnership working and public participation is health planning in the ‘new NHS’ may be explained, The literature review discusses key theories and models of community participation, power and policy implementation which informed the development of my key research questions and strategy. A review of the global, national and local influences upon a community participation in health planning is supplemented with primary research in the form of a detailed case study of one locality’s response to the national requirement to involve the public in the development of their HImP. A multi-method case study was employed using the following methods of data collection: observation, interviews, questionnaires and documentary analysis. The research presented identifies a number of issues as significant in affecting a locality’s approach to public participation, including: power; the organisational cultures(s) within the HImP partnership; the attitudes and capacity of those charged with developing participatory activities; and the impact of national priorities on local flexibility to respond to community identified priorities. The application of Alford’s (1975) structural interests theory to the findings provides a useful framework for assessing power relations and understanding why the HImP fails to represent community interests in the way that had been hoped. A number of recommendations are made to facilitate participation in health planning in the future, including: the need to address the national culture of risk avoidance; the need for better training in public participation skills for personnel charged with developing participatory opportunities; and the need for a mandatory performance framework related to community participation as a mechanism to ensure that participation issues are given the same attention as other nationally monitored issues.