This Ph.D. identifies the spatial structures associated with Ireland’s economic geography through an analysis of travel-to-work patterns. In doing so it applies, within the Irish context, novel techniques to identify local labour market areas using data that, heretofore, were unavailable to researchers in Ireland, i.e. detailed spatial interaction data describing the journey to work. The primary aim of this thesis is to address a research lacuna concerning labour and labour market areas within the field of economic geography in Ireland. This research augments our understanding of the spatial structure of Ireland’s economy through the identification of local labour market areas and elucidates the geographies of who works where and places these within an international context. This, in turn, facilitates a detailed evaluation of Ireland’s ‘National Spatial Strategy 2002 – 2020: People, Places and Potential’ (NSS). The content of this strategy raises fundamental geographic questions concerning who lives where, where they work and the spatial structure of those functional areas associated with cities and towns in Ireland. The thesis explores these issues through the dual conceptual lenses of geographies of labour and labour geographies. In additional to these theoretical considerations, the research is guided by three broad objectives: a) the identification of local labour market areas, b) to enhance the effectiveness of spatial policies in Ireland concerned with economic development in general and those affecting labour processes in particular by critically engaging with the concept of polycentricity, and c) to empirically evaluate selected spatial concepts that are central to the NSS. In addressing these objectives the thesis makes a significant contribution to both economic geography and spatial planning. It provides a comprehensive evaluation of the NSS and provides new insights into the geography of local labour market areas in Ireland, whilst also providing a methodology that overcomes the central criticism of the technique used in previous studies identifying labour market areas.