In interviewing security experts for our July cover story on cargo security, I learned about some of the latest tricks being used by cargo thieves:

* Walking down a line of tractor-trailers and opening unsecured trailer doors to see if the load is worth stealing.

* Backing a tractor under a dropped trailer and driving off with it.

* Staking out locations where truckers pick up high-value freight, then following the truck to a truckstop or rest area. After the driver is out of sight, the truck is hot-wired or the ignition quickly swapped out and the whole rig driven off.

* Striking up conversations with drivers at truckstops or on the CB to find out if they're hauling something valuable and where they're taking it.

* Causing a minor accident with truck. While the driver is distracted, the trailer door is broken into.

* Before a rig leaves a warehouse with a high-value load, marking the trailer with a big X to alert members of the gang which trailer to steal.

* Damaging a light on a targeted trailer so the driver will have to pull over and get the light fixed, at which point thieves steal the load or hijack the rig.

* Posing as the legitimate driver arriving to pick up a load. When the real driver arrives an hour later, the thief is long gone.

* Bidding on brokered loads, which disappear before they get to their destination.