You mean something like NAFI (USA), or RNZAC Instructor's Council (New Zealand), or I'm sure Oz would have their own equivalent...England must do, surely...
A worldwide one? That would be useful, not just for legal advice but also "How-to" information, what to look for when teaching__________, that kind of thing. Standardising and assessing, philosophy differences and why around the world etc. Sounds like a great idea.
On rereading, are you only talking about an English/British one?