Title: RE: [ubl-ndrsc] Tag structure discussion Mark, The value of a structured ID is that it allows one to compare/align the IDs of data from different systems (particularly legacy systems) using the power of a computer to find perfect matches in some cases or close matches in other cases. For example, if one company mapped their legacy data for <SupplierEnterpriseIdentifier UID= y.3_8 > and another company mapped their legacy data for <SupplierEnterprisePuchaserAssignedIdentifier UID= y.3_2.35.8 > a parser could flag the possibility that the data were in fact the same - based on the fact that y.3_8 is contained within y.3_2.35.8 and by applying the rules of UDEF where both contain the same representation term (identifier) and both contain the same object term (supplier enterprise) - there is a possibility that the two are semantically equal. Without intelligence in the UID, an automated comparison/alignment would be much more difficult. A major task when two new trading partners are attempting to conduct business with each other is the effort associated with aligning data between their differing systems. I would argue that a important part of the audience that will make ebXML fly are the large (Fortune 1000) companies and government organizations that have substantial investments in legacy systems. The vast majority of these large companies and government organizations will be relying on their legacy systems and will need to find ways to simplify the comparison/alignment of those systems to those of their trading partners. I suggest that structured IDs such as offered by UDEF is the way to simplify the alignment or comparison process. Ron Schuldt