The aviation sector must reduce its emissions if we are to protect ourselves from severe climate disruption. ICAO has suggested several options, including several non-market based as well as a global market based measure to reduce emissions in the aviation sector. Any market based solution must go beyond pure offsetting. Only a cap-and-trade scheme with a stringent cap and a limit on the use of offsets, combined with an ambitious set of technological and operational measures, will deliver actual emission reductions in the sector. This briefing paper by Carbon Market Watch discusses the range of market based measures under negotiation at ICAO.