The discussion around request information, queries for additional information on an original request, and bundling information in a request raises an ongoing issue around communication for this instance of requesting PAO that is seen in other orders that require some level information to determine if the request is supported and justifiable for payment once provided. For ease of use, known required information to support the request should be provided as a "shall" requirement so the requestor provides adequate information to satisfy the request. initially, there may be inadequate information required so that additional information is needed and, over time, that information may be added to the "shall" requirment in an interative manner. The end goal being to provide sufficient information for the request, authorization and payment in as complete a manner as possible to reduce back and forth communication threads. The challenge is to be as complete as possible so that fragmented information is avoided-so if additional information is requested, it be iterated on the original request so that a complete picture is provided as the last state rather than an initial request and fragments of communication back and forth. It appears that this is the intent of the messaging exchange here and the model should be applied evenaly across IGs wehre applicable so the goal of complete and clear communication is achieved in these requests (orders, referrals, consultations and so on) in the FHIR specificaitons.