I am writing this on behalf of a friend of mine who is about to embark with her soon-to-be-new husband on a couple of years of world travel. They are hopping from continent to continent as seasons change. They will not be making that many flights, but when they do they will be very long ones. They are not going to be staying in hotels that accrue points, nor using credit cards too often. They will officially stay US residents during this entire stretch.

Right now, their itinerary is Chicago-Miami-Quito in November, Rio-SE Asia (starting in DEL or or BKK or SIN) in March, back to Costa Rica in June, then over to Europe and then Australia and New Zealand in the fall of 2001.

What is the smallest set of FF programs that will catch the widest variety of airline miles most efficiently? Obviously, they'd like to stick with 2-3 plans at most as they're only going to earn 20-40k base miles per year.

Given what I know, I'm about to suggest UA/AS/AA as primary accounts. That should cover all of the major intercontinental carriers except the SkyTeam group and LatinPass.

But I suspect that some of you out there can improve on this strategy. Thoughts??