The economic impact of the marine economy is poorly understood at both a national and regional level in Ireland. A recent paper by estimated the economic value of the marine sector for Ireland at the national level. This paper presents a follow up analysis of the Irish marine sector at the regional level for 2007. The paper examines the impact of the marine sector in addressing regional disparities in Ireland, and the key marine sectors that drive regional economic performance within the marine sector. The analysis finds that in absolute values Dublin and the South West provide the highest levels of marine GVA, however, as a percentage of regional GVA, the marine sector is more important in the West and South West region. In terms of employment, the West and South-West provide the highest levels of marine employment, and this relationship is maintained when one examines marine employment as a percentage of regional employment. Finally, productivity rates for the sector were highest in the Dublin region. However, productivity in the marine-based sector was higher than the overall regional rate for five of the eight Irish regions.