Generally selecting a reasonable flight, but I see AA and UA fares that fall into the reasonable area quite often. We have global agreements with most of the chains I think, but I know for sure with Marriott. Last time I checked in at a Hilton I was upgraded to the concierge level so I don't know if that was because of our corporate program or I got lucky... apparently I was the only one upgraded out of the other people that were staying there. (I never asked for an upgrade, but I did get in extremely early and asked to check in early so I could grab some sleep since I flew in on a red-eye.)