The paper explores the nebulous concept of heritage in order to highlight issues relevant to the revitalisation and management of historic naval waterfronts. A model separating supply and demand sides, and further subdividing each side into political, social and economic structures, is used as a framework for analysis. The whole is set within a perceptual filter, and interpretation is subsumed within social structure. The model is applied to heritage concepts at Portsmouth Dockyard and to the legacy of naval defence in the neighbouring coastalzone. From the review of all three structures it is shown that economic considerations are increasingly powerful on both the supply and demand sides, as sovereignity passes to customers who are less interested in authenticity and architectural quality than in securing value for money. Issues and implications arising from this trend, and relevant to naval heritage planning and management, are identified.