The usual methods of delivery are by hand, mail, courier, electronically or by fax.

If the delivery method is agreed to in the purchasing documents then they must be delivered accordingly, provided it is legal. Failure to do can result in the agreement being null and void.

Purchasing documents usually specify a method of acknowledgment and acceptances. Contracts often require both parties to sign the original and each party retains a copy. A purchase order typically requires a written document stating receipt and acceptance of the terms and conditions.