The Korea–US FTA (KORUS FTA) has been one of the most contentious issues in Korean society because it is expected to have a tremendous impact on each of the economic agents. To investigate the macroeconomic effects of the KORUS FTA, two related general equilibrium approaches are used in this study. The static general equilibrium modeling focuses on efficiency gains from resource allocation. The productivity gains general equilibrium model, however, takes account of dynamic efficiency impacts from competitive effects and investment in the economies over time. The latter can be as important as or more important than the direct trade liberalization effects. (The rest is omitted.)