Book excerpt: The Indonesia–Malaysia–Thailand Growth Triangle (IMT-GT) comprises five priority economic corridors that are key geographic areas for subregional economic cooperation under the IMT-GT. This Indonesia country report presents the findings of a study that reviewed and assessed the four economic corridors that directly connect to Sumatera. The report provides data and analysis on these four corridors with a focus on physical connectivity, cross border trade, and value chains. The report also discusses how the corridors could be reconfigured to expand their reach into more Indonesian provinces and proposes the route for a new economic corridor.