Hi Lou and Council, I've been looking around for a TEI ODD file where I redefined content models. Mostly I just add/delete elements/attributes/classes which isn't really changing. Finally remembered I had changed some content models in my tei_corset ODD. This was a mass-digitisation ODD for the Stationers' Register project where the keying company was willing to use any XML schema but would charge per kilobyte of output. So I renamed everything to be shorter names, etc. in a tei_corset namespace which over a lot of text input saved us money and was easy to convert back. Where I used any relax ng in this it was fairly minimal and the conversion able to be done automatically with no problems: a) to rename <TEI> to be <file> and say that its content model was just <teiHeader> and <body> (both renamed elsewhere) Old ODD: https://github.com/jamescummings/conluvies/blob/master/tei_corset/tei_corset... Pure ODD: https://github.com/jamescummings/conluvies/blob/master/tei_corset/tei_corset... This just changes to two <elementRef>s. b) to rename <teiHeader> to be <header> and give it a content model of <title> followed by zero or more model.pLike Old ODD: https://github.com/jamescummings/conluvies/blob/master/tei_corset/tei_corset... Pure ODD: https://github.com/jamescummings/conluvies/blob/master/tei_corset/tei_corset... This just changes to an <elementRef> followed by a <classRef> c) for various reasons some empty elements were changed to allow text content. For example <gap> was renamed <gp> and had a content of rng:text Old ODD: https://github.com/jamescummings/conluvies/blob/master/tei_corset/tei_corset... Pure ODD:https://github.com/jamescummings/conluvies/blob/master/tei_corset/tei_corset... rng:text just becomes <textNode/> d) exactly the same thing for <space> renamed <spc>: Old ODD: https://github.com/jamescummings/conluvies/blob/master/tei_corset/tei_corset... Pure ODD: https://github.com/jamescummings/conluvies/blob/master/tei_corset/tei_corset... The resulting schema validates against the files I had. I did have to change some other things in the ODD, but these had to do with the moving of rendition things into att.global.rendition from att.global. (Since this ODD was 3 or 4 years old.) I converted the Pure ODD to HTML and everything worked as expected. Clearly not an exhaustive test of all of the functionality of Pure ODD, but just another confirmation that migrating to Pure ODD is able to be semi-automated and for most people's low hanging fruit doesn't introduce any major problems. -James -- Dr James Cummings, James.Cummings@it.ox.ac.uk Academic IT Services, University of Oxford