[specialist]

I've been a part of a few standards/interop efforts. Postel's Law and my experiences indicate those efforts are non-starters.

I also participated NHIN's first competitive interop whatever it was called. (We were sub to Northup Grumman. Our team won. Yay. That recognition plus $3 will get you bad cup of coffee.)

The secret to interop is to ignore the standards. No one else cares, so why should you?

For inbound, just capture whatever is sent, use web scrape style tools to extract the bits you care about. For outbound, manually create payloads that work (maybe with SOAP-UI and then tweak), turn them into templates.

If you're a monster org like Boeing or Toyota, you can rule by fiat. Everyone else has to fake it.