The implementation of the National Single Windows and the ASEAN Single Window together with the reform and modernization of customs will jointly redress the highly disparate customs environment in the region, thereby engendering faster and more predictable flow of good within the region and from the region and the rest of the world. This initiative required a change of essential features of customs control, expressed in customs procedure and practices. Foremost of all, making them compatible and interoperable is a key to enhanced ASEAN connectivity. Indeed, the deepening and widening of the regional production network in the region, which means larger volume of time sensitive imports moving within the region, necessitates more efficient and consistent customs service in the ASEAN Member States. The implementation of the National Single Windows and the ASEAN Single Window facilitated the streamlining of processes and procedures, engenders tight coordination of related government agencies And trade-related service providers in the private sector, and fosters greater transparency and predictability on trade-related rules, regulations and procedures. All these redound to faster, easier, more predictable, and more cost effective movement of goods that would ultimately benefit the ASEAN Member States and lead to deeper ASEAN economic linkages.