Foreword by Airports Council International World In its latest Airport Traffic Forecasts 2025-2054, ACI World predicts global passenger traffic will reach 10.2 billion passengers in 2026 and 18.8 billion by 2045, confirming sustained long-term demand growth and underscoring the role of aviation — and airports in particular — as sources of stability that enable trade, mobility, tourism and global connections. At the centre of the aviation system, airports are more than physical infrastructure; they serve as economic anchors and community gateways, sustaining supply chains, supporting jobs and maintaining vital links that underpin well- functioning economies and social cohesion, even in times of uncertainty. In this context, geopolitical shifts, social change, climate impacts and broader uncertainties should not slow progress, but instead serve as a catalyst to reaffirm ambition, accelerate action and embrace the transformations needed to build a resilient, sustainable and innovative aviation sector. Ensuring the sector can grow sustainably is therefore not only an industry priority, but a global economic imperative. The air transport sector continues to make progress towards net-zero carbon emissions by 2050 and it is important to recognize how much has already been achieved. As this Global Aviation Sustainability Outlook 2026 demonstrates, airports worldwide are delivering concrete results: expanding sustainable aviation fuel (SAF) distribution, improving energy efficiency, electrifying ground operations, exploring hydrogen projects, strengthening cooperation programmes and increasing participation in the ACI Airport Carbon Accreditation programme, managed by ACI Europe. This progress across airports and the wider aviation ecosystem is real, measurable and deserving of recognition.With the International Civil Aviation Organization (ICAO) leading the collective ambition of states, these efforts help the sector to remain focused and move decisively forward. Yet the path ahead remains uneven and the challenges are significant. The next five years will be critical in keeping air transport on track for decarbonization.1 This will require accelerated action and collective effort across the aviation industry and governments, supported by substantial, long-term commitments from the finance and energy sectors. SAF is central to all decarbonization pathways and must remain a primary focus of action. While the steady growth of the SAF market is encouraging, a much faster scale-up is needed. At the same time, the aviation sector, including airports as energy and infrastructure hubs, will require access to sufficient, reliable, renewable and low-carbon energy to meet growing demand. These decarbonization efforts must go hand-in- hand with adaptation and resilience, as climate impacts are already increasingly affecting airport infrastructure and operations. Meeting future demand and shaping a next-generation, future- ready aviation sector will require significant, well-coordinated investments to enable long-term, economically sustainable air transport infrastructure. This report reflects both the urgency of the moment and the opportunity ahead. It rightly underscores the need for pragmatic, actionable strategies and sustained collective delivery. Airports will remain central to this effort, serving as pillars of stability, innovation and coordinated action for the global aviation system and the generations of travellers and communities to come.Justin Erbacci Director General, Airports Council International (ACI) World Global Aviation Sustainability Outlook 2026 5