"Document models can be created that have nested namespaces, and Teiid contains code to use different namespace prefixes for nested elements. However at least for my simple test case (see attached) the generated mapping document does not contain any namespaceURI information for the elements - it only has the namespace declarations. It would appear that the logic in MappingDocumentFormatter is not correctly associating the prefix/uri with elements at least for a simple hand made document model. I don't know if things are different when starting with a schema." - SteveH