Abstract: A transaction processing system facilitates the buying and selling of commodity products by establishing a single documentary record for the transaction, requiring approval of variables introduced into the transaction. The parties register and agree to a standard contract of terms. For each transaction, the unique data for that transaction is entered by the parties and then must be affirmatively approved. Next, a schedule for delivery of the product is developed in conjunction with an overall schedule for product delivery for all of the current transactions. After the product is delivered, a product delivery report is provided from the delivery asset specifying the volume of the product, its composition, and shipment. This information, in conjunction with the transaction contract, are utilized to produce invoicing data. The parties must affirmatively approve the invoicing data prior to the production of payment statements by the system.