Marty, I don't disagree with your premise. We do need to avoid the word OPTIONAL unless that is really what we mean. Doug/Chris' Issue 15 concerns OPTIONAL in relation to the Role element. At the bottom of the issue, it also says there are other instances... I just went through the document again and I don't disagree with any of the instances where we use OPTIONAL. Ping/Pong (w/ or w/o signature), Message Status, MessageOrder are all truly OPTIONAL items for implementers. The only one I'm not sure about concerns Transfer Encoding on HTTP (I'm too lazy to research this at this time of night). Outside of the definitions, we use the word *OPTIONAL* 13 times and *optional* 3 times (twice concerning the id element -- which maybe is not truly optional). Perhaps the problem is in section 1.1.1 and our definition of OPTIONAL? It says: ... An implementation which does not include a particular option MUST be prepared to interoperate with another implementation which does include the option, though perhaps with reduced functionality ... which we do by supplying the NotSupported Error. Regards, David.