As COVID-19 vaccination programs roll out across the world, many economies in the Asia-Pacific region have established their own domestic digital COVID-19 certificate systems. However, as there are various systems for verification of vaccination status, economies have the challenging task of verifying proof of COVID-19 vaccination. As APEC economies are at different stages in developing domestic digital COVID-19 certificate systems, an interoperable approach to verify vaccination status of these travellers is important to facilitating border re-openings and reconnecting economies across the Asia-Pacific region. To support the diversity of governmental approaches and technologies in use throughout APEC, this project aims to explore ways APEC member economies can share technical specifications of their vaccination certificates to verify the authenticity of vaccination certificates issued by member economies, with a view to create interoperability among interested APEC member economies  while avoiding affecting and discrimination against travelers from other non-participating APEC member economies. The sharing of technical specifications and trial of interoperability of vaccination certificates among APEC economies are on a non-binding and voluntary basis, and fully respecting and observing economies’ domestic policy and containment measures against COVID-19, including quarantine policies for cross-border travelers.