According to Wikipedia, it's:
Quote:Flying Blue is the frequent flyer program of Air France and KLM. In June 2005, the frequent flyer programs of Air France (Fréquence plus) and KLM (Flying Dutchman) were combined to the Flying Blue program after the two companies merged into a single airline. Apart from KLM and Air France, Flying Blue is also the frequent-flyer scheme of various carriers which used to share Air France's Fréquence plus or KLM's Flying Dutchman schemes, e.g. Kenya Airways (partly owned by KLM), Aircalin (partly owned by Air France), etc. On June 15, 2007, it also became the loyalty scheme of Air Europa as the company was moving towards becoming an associate member of SkyTeam sponsored by Air France (associate members have to abandon their own frequent flyer program and adopt that of the sponsoring carrier). Flying Blue members can earn and spend mileage points on flights and services of Air France-KLM, other companies of the SkyTeam airline alliance and assorted other financial, travel, and transportation companies.