Question for the protocol experts. If one wanted to write one's Clan Chief, is there a particular form that one would follow in addressing the letter, salutation, etc.? Specifically, does one address him with his peerage title (assuming he has one), or is there a form amongst the Scots used when addressing him in his role of Chief?

Is my question clear or is everyone as confused as I suspect they might be?

As a side note, I have no specific chief in mind, just curiosity on a general point of protocol.