A purchase requisition (PR) is an internal document used by an employee to request the purchase of goods or services and initiate the purchasing process. A purchase order (PO), however, is issued when the requisition has passed evaluation and approval. A PO is an official order issued by the company’s procurement department to a supplier, authorizing the purchase and specifying the transaction terms. Issuing a purchase order is the next logical step after approving the purchase requisition. Nowadays, companies implement purchase order requisition software to process both types of documents automatically.