Academic libraries play a valuable role in supporting the learning and teaching objectives of its parent institution and responding to the learning and research needs of its users. However recent technological, social and economic developments have seen the central position that the library once enjoyed as ‘the heart’ of the institution being eroded. As a counter to the difficulties presented by changes in the digital and information landscape, changing user behaviour, and reduced library resources, academic libraries are increasingly adopting marketing principles and techniques in order to demonstrate their value, communicate with their users, redefine the library service and justify library funding. The purpose of this dissertation is to investigate the nature and practice of marketing in Irish academic libraries. This study contains findings derrived from semi structured interviews undertaken at five university and institute of technology libraries in Ireland. The findings are analysed with reference to key library documentation which provides for a more detailed understanding of the nature and purpose of marketing in these institutions. The key findings of this study reveal that there is no standardised or uniform approach adopted by these libraries in relation to marketing. Marketing at the five libraries can be described as being formal and planned on one hand to being informal and ad hoc on the other. Based on the findings it is evident that those libraries who adopt an informal approach to marketing are concerned with tactical marketing activities rather than a long term strategic perspective. Marketing has yet to be developed as a key strategic service activity for the majority of the library services in this study.