The term cross-docking is used to describe processes where stocks from incoming goods are not stored but instead are fed directly into the outgoing goods process. For cross-docking, a distinction is made between processing inventory-managed material and HU without inventory information.

• For cross-docking of inventory-managed material, additional processes must often be initiated since the quantities available in incoming goods do not usually correspond exactly to the quantities required in outgoing goods. Example processes are the storage of residual quantities, the retrieval of shortages and the cancellation of retrieval tasks that are replaced by cross-docking.
• For cross-docking of HU without inventory information, no inventory management based on material takes place. Only the HU are identified, managed and controlled based on their destinations (customers/loads/deliveries). This means that material quantities are not relevant.

In addition to inventory information, the process trigger is of crucial importance for cross-docking. Firstly, a distinction is made between:

• unplanned cross-docking
• planned cross-docking

In unplanned cross-docking, the WMS recognises whether the stock items in incoming goods qualify for cross-docking during the incoming goods process or the outgoing goods process.

• unplanned cross-docking in the incoming goods process:

During creation of the warehouse tasks for storage, a check is carried out to see if stock items can be used for deliveries. In case of a match, crossdocking takes place.

• unplanned cross-docking in the outgoing goods process:

During creation of the warehouse tasks for retrieval, a check is carried out to see if any matching stock is being delivered or available in incoming goods. In case of a match, cross-docking takes place. In planned cross-docking, the decision as to whether or not cross-docking will take place is taken prior to the physical arrival of the material.

Planned cross-docking is subdivided into:

• goods allocation

During goods allocation, a decision is made in the ERP system to carry out a cross-docking. The deliveries and delivery orders affected by the crossdocking are communicated to the WMS. In direct cross-docking, the materials are distributed untouched. In flow-through, however, the material is relocated from the incoming goods area to a repacking area before being made available in the outgoing goods area.

• transport cross-docking

In contrast to the other cross-docking processes, transport cross-docking has no impact on the process within the warehouse. Instead, it impacts the transport process to the goods recipient. In this case, the WMS draws on route information to decide during the outgoing goods process whether goods are transported to a goods recipient directly or via one or several hubs.