The ten Southeast Asian economies reached a milestone on 31 December 2015, when they announced the formation of an ASEAN Community. Although this includes three pillars - ASEAN Political-Security Community, ASEAN Economic Community (AEC) and the ASEAN Socio-Cultural Community - it is the economic pillar that generates immense debate, due to its expected quantifiable benefits to member countries. This book, thus, focuses on the ASEAN Economic Community and seeks to explain the need for building domestic consensus within the member countries. It starts with an overview chapter describing the current achievements of the AEC. It then explores possible explanations for the achievements/non-achievements and offers a hypothesis on conflicting economic interests in a country as one possible explanation for gaps in implementation. This is because any form of economic liberalisation brings with it the winners and losers, thereby raising resistance to liberalization measures and slowing down the implementation process.