Royal Decree 1368/1987, dated 6 th November, regulating titles, forms of address and honours pertaining to the Royal Family and to the Regents
Chapter One: Of the Royal Family
Article 1
1. The holder of the Crown shall be termed The King or The Queen of Spain and He or She may use the other titles pertaining to the Crown, as well as the other peerages belonging to the Royal Family. He or She shall be addressed as His or Her Majesty.
2. The King of Spain's wife, whilst She remains His spouse or stays a widow, shall be termed The Queen and be addressed as Her Majesty, being entitled to the honours pertaining to Her Dignity, pursuant to the law of the Realm.
3. The husband of The Queen of Spain, whilst he remains so or stays a widower, shall be entitled to the Dignity of Prince. He shall be addressed as Your Royal Highness and be entitled to the honours pertaining to his Dignity, pursuant to the law of the Realm.
Article 2
The heir to the Crown shall, as from his or her birth or as from the moment the fact giving rise to such entitlement arises, possess the Dignity of The Prince or The Princess of the Asturias, as well as the remaining titles traditionally attached to the Successor to the Crown and be entitled to the honours pertaining to him or her by virtue thereof. He or she shall be addressed as Your Royal Highness. The same Dignity and form of address shall correspond to his or her spouse, with the honours deriving therefrom, pursuant to the laws of the Realm.
Article 3
1. The King's sons and daughters not possessing the Dignity of Prince or Princess of the Asturias, as well as the children of the latter Prince or Princess, shall be Infantes or Infantas of Spain, respectively, and shall be addressed as Your Royal Highness. Their spouses, whilst they continue being so or stay a widower or widow, shall be entitled to the form of address and honours The King, as a gracious decision, may grant them, pursuant to the powers vested upon Him by paragraph f) of Article 62 of the Constitution.
2. Likewise, The King may grant the dignity of Infante or Infanta and the form of address of Your Royal Highness to those persons he shall deem fit of such a grace given the exceptional circumstances that concur.
Chapter Two: Of the Regency
Article 5
The persons exercising the Regency shall be addressed as Your Highness with the same honours as those laid down for The Prince of the Asturias, unless entitled to honours of a higher rank.
Chapter Three: Of the peerages pertaining to the Royal Family
Article 6
The use of peerages, pertaining to the Royal Family, may only be authorised by the Holder of the Crown to members of His or Her Family. The conferment of use of the title shall be considered a grace of a personal nature and for life.
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