May 1981 — American Airlines launches AAdvantage, the first mileage-based frequent flyer program in history. Days later, United Airlines introduces its Mileage Plus program.

May 1982 — American AAdvantage partners with British Airways.

May 1983 — Aloha Airlines follows Hawaiian Airlines and launches its own frequent flyer program: Aloha Pass.

May 1986 — Delta Frequent Flyer offers members automatic credit tracking with car rental partners.

May 1986 — People Express, along with partners Frontier, Britt and PBA, introduces a frequent flyer program called Travel Rewards.

May 15, 1987 — The introduction of the HHonors program is unique in that it is launched not only as a reward program for loyal Hilton customers, but as a fundraising effort for the 1988 U.S. Olympic Team. Hilton makes a contribution to the Olympic Team every time an HHonors member checks into a hotel. Hilton estimates that over $1 million was contributed in support of America’s aspiring Olympic athletes. In fact, it was this Olympic tie-in that led to the Bronze, Silver and Gold elite levels, and among the awards offered in the original award chart was a VIP visit for two to the U.S. Olympic Training Center in Colorado Springs, Colo. Cost: 200,000 points.

May 1995 — Delta Air Lines, citing a need to have a distinctive moniker for its frequent flyer program, changes the name from Frequent Flyer to SkyMiles.

May 1997 — Marriott consolidates its three loyalty programs — Marriott Honored Guest, Courtyard Club and Fairfield INNsiders Club — into one new program — Marriott Rewards.

May 1997 — United Airlines, Lufthansa, Thai Airways, Air Canada and SAS form the Star Alliance.

May 1, 2002 — The Norwegian Competition Authority prohibits SAS EuroBonus from awarding frequent flyer points on domestic Norwegian routes. EuroBonus is still allowed to award frequent flyer points on international trips and to offer its customers any kind of service, including bonus trips inside Norway, in exchange for frequent flyer points already earned. The Norwegian Competition Authority views the intervention as an essential step towards reopening the Norwegian market for competition, claiming that EuroBonus works as a barrier to entry.

May 2005 — Priority Club logs an industry first by allowing members to redeem points for stays at any hotel — even competitors’.