The PO requisition lines created during order entry for vendor shipments are converted to purchase orders using the Requisition Management program. Vendor ship requisition lines may be edited in order to change the default price or vendor recorded in the requisition. Once the requisition lines have been modified as required, the operator can convert the requisitions to purchase orders by selecting the lines and pressing a key. Relevant information is moved from the sales order into the purchase order as the purchase order is saved. The Purchasing system does not allow the operator to delete requisitions or PO lines if the PO lines are linked to a valid sales order. The system will warn the operator that they are trying to delete a linked purchase order document and instruct the operator to first delete the sales order. If a vendor ship or special order requisition or purchase order needs to be cancelled, the operator should delete the sales order line. This will automatically delete any requisitions for the sales order line. Purchase orders for the sales order are not automatically deleted as the vendor may have already shipped the merchandise and further action may be required. Since Vendor shipments are tied to individual sales orders and since the system automatically transfers information from the sales order into the purchase orders for the sales order, vendor shipments from multiple sales orders may not be combined on the same PO.