Make sure you do your homework before you go and verify your LP account information has been correctly inputed into your PNR(s) before you go. If you have an itinerary with multiple airline segments, you have to add a seperate entry into the record for each of the airlines(a long process). If you have everything correctly posted in the PNR, you will save yourself lots of time (and in the case of TWA and US Air, lots of grief)upon check in.