Loading a truck seems simple to me but Pat Penman, director of global environmental and safety actions at SC Johnson, called it a "science." Turns out it's not just a really simple game of Tetris with lots of cube shaped-packages. You have to consider things like "consistently hitting a trailer's maximum weight."
For example, a truck load of SC's Ziploc bags might be too light, so SC is now mixing products like Pledge or Windex in those shipment to get to the optimum weight. The considerations are not just in the back either. If it's just a day trip, SC uses a truck without the sleeping compartment to save weight. Industry Week links to a game you can play (They ask for your last name and e-mail but no e-mail confirmation is sent. You can start to play right after entering the data) with some of the other considerations like axle weight and products that must ship.
Sure, years ago, this would have been considered logistics or efficiency stuff but today it's "green." It's also interesting and kinda cool to read about it. I have gained a whole new respect for packing the trunk. More than I ever thought I would have.