Transport Infrastructure Impact Assessment to Regional Economy: Methodology Framework and Comparative Analysis

Planning and appraisal of transport infrastructure projects involve complex challenges due to their widespread economic and social implications. This paper suggests a comprehensive methodological approach to the assessment of the socioeconomic impacts of such projects in the context of regional development. By coupling Input-Output (I-O) analysis with Key Performance Indicators (KPIs), the suggested methodology supports systematic examination of the interlinkages among direct, indirect, and induced effects on employment, income, and sectoral development. The approach is specifically designed for ex-ante use, allowing decision-makers to forecast economic outcomes before the launch of projects and to optimize investment plans in accordance with policy goals. The methodology is applied to two different types of infrastructure in Greece: a motorway network and a tourist port, thus illustrating the method’s usability and applicability. By taking an integrated view, this research clarifies interdependence between diverse infrastructure investments within regional economic systems and their contributions to overall development goals. The method supports evidence-informed planning, enhances transparency of the appraisal of infrastructure investments, and provides a replicable tool to inform strategic decision-making in diverse territorial and sectoral contexts.