Last year, the assembly of the UN’s International Civil Aviation Organization agreed to set an aspirational goal of net-zero emissions by 2050, reinforcing targets and commitments made already by both industry and individual states for the sector. While net zero provides a common goal for aviation, it comes with a recognition that this sector is likely to be one of the hardest to abate. Most stakeholders agree that meeting this challenge will require a broad approach, encompassing both operational efficiencies and changing the ways we fuel flight.