The Lord has jurisdiction over all heraldic matters in Scotland and maintains heraldic records.
William Sellar, 72, the current and 37th Lord Lyon, has been in the post since 2008 but will step down from the position in December.
The Lord Lyon is responsible for coats of arms and flags and anyone wishing to use a coat of arms must apply to that office for permission.
In 2008 American billionaire Donald Trump fell foul of the court of the Lord Lyon after using an unregistered emblem to promote his controversial golf course, but was later given permission for use in 2012.
The Lord Lyon office also incorporates the ancient Celtic office of the High Sennachie who was responsible for verifying the genealogy of the King of Scotland and for crowning the King at his coronation.