PHX is an excellent airport on many fronts with just a few negative aspects. If you plan to transfer at PHX and want to switch airlines you will need to change terminals. This is not obvious but this is because very few people would want to do this since both Southwest and America West/USAirways have their hubs in T4. If you check luggage do not expect to find it waiting for you when you get down to baggage claim. Since PHX is a hub the volume of bags they process is enormous and the speed that passengers can make from the plane to the carousel will always result in a wait for bags. (Hint: Do not check bags!). T2 is very old and it is not attractive to look at. T2 is fast; from the car park to the airplane in fifteen minutes on some occasions including ticketing security and the walk. The T2 parking garage is right next to the terminal and the terminal is an older one full of airlines like TED so you can move right through it. And you will want to as there is no real reason to linger. T3 is fast; from the car park to the aircraft is again quick and easy. T3 is a vintage 1980's terminal but it has some very attractive artwork on the departures level and because of the hub in T4 for Southwest and America West/USAirways the remaining mainline airlines are usually on time and heading for their own hubs. T3 is also clean with plenty of seating although most of the airline clubs are now closed since 9/11. T4 is new clean and efficient. Lines in the ticketing level can be enormous but they move quickly. Security is usually pretty fast in T4 and the lines on the departures level move quickly there also exept on Spring Break. T4 has numerous dining options shoeshine and even art galleries. Passengers can walk from the Southwest side to the America West side without leaving the secure area. The travelators make a transit in T4 fairly painless. Sky Harbor has moved all the rental cars to an off-site condo facility to the southwest of the airport. The busses run very efficiently and they are not operated by the self-important Transit Police like at SJC but rather by helpful folks who want to transport you. The facility itself is huge but easy to navigate. Roads and Signage: The traffic flow around the three terminals is complex but the signs are very clear and accurate. Drivers new to Sky Harbor should be aware that the Rental Car facility is not AT the airport and that the traffic flow at T2 is different from T3 and T4 because it has a different orientation to the runways.