Limited to the commercial aerospace industry where a request is made for a PO to have Direct Delivery Authorization (DDA), which includes an Appropriate Arrangement (AA) between the PO and the Design Organization (DO). In this process the DO is responsible for ensuring the continuous updating of design and airworthiness data to the PO, whilst the PO is responsible for assurance that the manufactured article conforms to approved design and airworthiness data. The PO is responsible to provide airworthiness release documentation.