Security Of Desks and File Cabinets <-- click
There may be nothing in this brief article you don't already know, but refresh your memory anyway. When it comes to securing information, this topic ranks right up there with shredding and eavesdropping.
Necessity spawns invention...
At the start of my career an executive countered my suggestion that he clear his desk at night. "I have my paperwork in very specific piles. I can't be moving all of them every night."
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If you get any grief, ask your execs, "Would you leave a stack of twenties on your desk overnight?" ~Kevin
Photo (Click to enlarge.) - My worst case.