Using a title

• Since it comes from a sovereign and universal order of knighthood and is officially recognised, it is completely legal to use a title in all countries worldwide, as it is authorised by law. It may be mentioned on all documents, business cards, headed paper, written under signatures, in telephone directories, announcements, who’s-who, credit cards or any other personal or official document without any restriction. 
• It cannot ever replace a marriage or birth certificate, like any other title. With the agreement of a Prefect, it can be mentioned on a passport, under "used name".