Cross docking, or flow-through distribution, which eliminates storage in the warehouse and the subsequent need to pick stock to fill orders, can dramatically reduce labor and inventory carrying costs. The concept seems simple enough: Instead of unloading merchandise and putting it into the warehouse, just move it across the loading docks to other trucks and send the merchandise on to its intended final destination. Nothing to it. Is cross-docking really so simple? What are some of the complicating factors that make this seemingly simple concept challenging to implement?