Originally Posted by Romelle

Within a network, if you are flying on x and want to accumulate miles on y, theoretically all you have to do it enter your y number on the x ticket. There usually is a place for it via on-line purchases. If it is not apparent, it is possible to call after the ticket is purchased and get the right airline number to the ticket. I used to do it from Delta to NW. More recently have done it successfully with Malev and Aeroflot to Delta.

It is important though to check the fine print. Sometimes the lower fare classes don't work quite the same way. Air France to Delta makes me nervous, as I'm usually traveling on a t (or the equivalent lowest class) ticket fare. Continental, when it was part of Skyteam, used to only give 50% of the miles when one tried to get them posted to Delta.

Romelle