This chapter attempts to measure and analyze the economic interdependencies among China, Thailand, and Lao PDR made possible by constructing a three-nation international input–output (TNIIO) table. It is an international type of IO model that provides a compact and comprehensive accounting framework to quantify the economic inter-relationships among and between industries located in the three countries concerned. Applications such as linkage and impact analyses, as well as spillover and feedback effects, are presented and analyzed in terms of the economic interdependencies among the three countries. Linkages reflect the dependence of industries on one another in an economy and measure the potential stimulus that will be induced in other industries arising from an increase in activity in a particular industry. A Backward Linkage is a measure of the relative importance of an industry as a user of inputs from the entire production system.