Open skies, like open borders, facilitate exchange by keeping costs low and quality high through competition. This Brief IDEAS argues for an open skies policy for ASEAN. The Brief provides a basic overview of the levels of freedom of the air, an update on the inter-state aviation agreements in ASEAN, and policy recommendations to advance the ASEAN Single Aviation Market in light of a recently held high-level roundtable organised by Institute for Democracy and Economic Affairs (IDEAS) and the Economic Research Institute for ASEAN and East Asia (ERIA).