For each item ordered, the clerk checks to see if the item is available from the current stock. If the stock on the shelf is sufficient for the quantity ordered, then the clerk dispatches the item and updates the stock record. However, of the stock on the shelf that is not sufficient to satisfy the quantity ordered, the clerk whatever stock is available, creates a back order for the outstanding quantity, and updates the stock record. If an item is completely out of stock, then the clerk immediately informs the customer and creates a back order; at the same time, the clerk telephones the supplier to place an urgent order.