Increasingly managers in the public sector are being required to manage change, but many of the models of change which are available to them have been developed from private sector experience. There is a need to understand more about how the change process unfolds in the public sector. A case study of change in one local authority over the period 1974-87 is provided. The events surrounding housing decentralisation and the introduction of community development are considered in detail. To understand these events a twofold model of change is proposed: a short wave model which explains a change project or event; and a long wave model which considers how these projects or events might be linked together to provide a picture of an organisation over a longer period. The short wave model identifies multiple triggers of change and signals the importance of mediators in recognising these triggers. The extent to which new ideas are implemented and the pace of their adoption is influenced by the balance of power within the organisation and the political tactics which are used. Broad phases in the change process can be identified, but there is not a simple linear passage through these. The long wave model considers the way in which continuity and change feed off one another. It suggests that periods of relative stability may be interspersed with more radical transformations as the dominant paradigm guiding the organisation shifts. However, such paradigmatic shifts in local government may be less obvious than in the private sector due to the diverse nature of the former.