In the ECJ decision in the Air France-KLM case, the ECJ stated that the issue of tickets by an airline company is subject to VAT where the tickets issued have not been used by passengers and the latter are unable to obtain a refund for those tickets. After briefly highlighting the facts of the case, as well as previous views given on it before it was actually decided, in this article, the author focuses on the content of the decision and, more specifically, on the potential impact of the definition of “supply of services” given by the ECJ.