Thankyou all for your assistance with this. The core problem however remains. We are trying to map objects from out data structures into LandXML elements/attributes, and then into another product. How we do our mapping, naturally, makes perfect sense to us :) There seems to be some confusion (on our and our users part) when the second mapping is applied with data either not being as expected, or disappearing totally. I believe that LINZ, a major LandXML user, provides a document detailing what parts of LandXML they support, and how they interpret it. Has there been any move to encourage software providers/developers to supply this sort of information to the wider community? We do have this information available, although I suspect it may be difficult to find, and may not be particularly clear. Does anyone else see a need for this information to be readily available, and has anyone thought about a suitable format? Comments appreciated.... -- Hugh Dixon www.liscad.com