Mike -- This seems quite similar to the proposal I submited based on Type Descriptor. They have a schema for the physical representation and the instances of which (eg. recordInfo, fieldInfo etc) appear as annotations on schema elements , attributes etc. Suman Kalia IBM Toronto Lab WebSphere Business Integration Application Connectivity Tools Tel : 905-413-3923 T/L 969-3923 Fax : 905-413-4850 Internet ID : kalia@ca.ibm.com ----- Forwarded by Suman Kalia/Toronto/IBM on 01/28/2005 09:20 AM ----- mike.beckerle@ascentialsoftware.com Sent by: owner-dfdl-wg@ggf.org 01/28/2005 04:36 AM To dfdl-wg@gridforum.org cc Subject [dfdl-wg] Microsoft Biztalk Flat File Extensions Microsoft has a completely proprietary but otherwise DFDL-like thing in its bag of tricks too: see http://www.winterdom.com/dev/bts/BTSFFSchemaTut2.html