All invoices MUST have a purchase order referenced on the invoice. A purchase order can be obtained from the Purchasing Department and should be created prior to ordering and/or obtaining the goods. (Please contact the Purchasing Department directly for further Drew University policy and procedures on ordering.) Invoices that do not have a purchase order number on them will result in the vendor not receiving payment as well as potentially delaying the delivery of the purchase. An invoice should be mailed directly to the Accounts Payable Department from the vendor. Once received by A/P, it will be date stamped and mailed to the proper department for approval by the person authorizing the purchase (the same person who authorized the purchase order). Once the invoice has been approved, it must be sent back to Accounts Payable for payment processing.