The Member States of the Association of Southeast Asian Nations (ASEAN) and the European Union (EU) have adopted a comprehensive air transport agreement (CATA) to liberalize air services between their regions. The CATA is the first air services accord between two major regional trading blocs providing enhanced market access for both sides’ airlines and other mutual benefits. This article analyses the aero-political factors influencing the negotiation of the CATA, particularly the contentious issue of fifth freedom rights, given the huge presence of sixth freedom carriers in the ASEAN-EU market and the incomplete formation of the ASEAN Single Aviation Market (ASAM).