Hundreds of aircraft operators in Europe and around the world are scrambling to meet this Thursday’s deadline to complete the requirements for monitoring, reporting and verification of 2010 engine emissions under the European Union’s emissions trading scheme (ETS). Their efforts to complete the burdensome process have been made harder by delays and lack of clarity on the part of the authorities responsible for administering ETS in each of the 27 European Union member states. Many national authorities have given approval to the independent verifiers required to complete the reporting process only within the last few weeks, causing a verification bottleneck. Operators assigned to report to authorities in the UK and Ireland found that these states are requiring reports to be filed via online portals that contain software errors, necessitating that the emissions data be entered manually. Other states allow operators to upload emissions in the standard Excel spreadsheet format used by the ETS support facility. This support facility, which is supposed to make ETS compliance more straightforward for so-called small emitters, was launched only on March 1–less than a month ahead of the deadline. Spain unilaterally brought forward its reporting deadline to February 28. It remains to be seen whether European authorities will exert their powers to penalize operators who don’t meet the deadline. Ultimately, aircraft can be barred from landing at or taking off from European Union airports if their operators have not met their ETS obligations.