In December 2015, ASEAN Member States (AMS; 10 countries in Southeast Asia) announced launching ASEAN Community, including ASEAN Economic Community (AEC). - The AEC's establishment in 2015, in fact, was progress toward, rather than a completion of, economic integration. - Complete integration will not be an easy task to achieve in the short term, given the fact that AMS are greatly diverse in terms of economic structure and development levels. However, their aspiration to reach the completion of AEC will push them to realize their goals soon. Therefore, Korean firms and the government must be ready to cooperate with the new economic bloc representing a population of 600 million, and $ 1.7 trillion in GDP. - There exist disparities among firms in terms of their awareness of or information on the AEC. - Although the Korean government's response to the AEC launch should be more strategic, the action it took last January was tentative. The Korean government should prepare more concrete strategies in response to the changes in the ASEAN region.