This paper presents three approaches to the evaluation of cross-border transportinfrastructure in the Greater Mekong Subregion (GMS). First, it estimates benefit-cost ratios for selected segments of economic corridors. The results indicate differing degrees ofeconomic viability among different corridors. Second, it presents a panel data analysis on
how economic corridor developments have impacted living standards at subnational level. The results indicate that economic corridors in the GMS as a whole show a positive neteconomic impact. Third, it presents a gravity model analysis on how economic corridors have affected intra-GMS trade. The results indicate positive effects of the development of economic corridors on intra-GMS trade in intermediate goods, especially for electric machinery.