A blanket order is a contract under which a vendor agrees to provide goods or services on a purchase-on-demand basis.  Therefore, a sum of money has been set aside for a specific vendor that a department may use on a recurring basis in order to purchase services and consumable supplies for a specified period of time.  The contract generally establishes prices, terms, conditions, and the period covered (no quantities are specified); shipments are to be made as required by the purchaser.