Section 56
1. The King is the Head of State, the symbol of its unity and permanence. He arbitrates and moderates the regular functioning of the institutions, assumes the highest representation of the Spanish State in international relations, especially with the nations of its historical community, and exercises the functions expressly conferred on him by the Constitution and the laws.
2. His title is that of King of Spain, and he may use the other titles appertaining to the Crown.
3. The person of the King is inviolable and shall not be held accountable. His acts shall always be countersigned in the manner established in section 64. Without such countersignature they shall not be valid, except as provided under section 65(2).

Section 57
1. The Crown of Spain shall be inherited by the successors of H. M. Juan Carlos I de Borbón, the legitimate heir of the historic dynasty. Succession to the throne shall follow the regular order of primogeniture and representation, the first line always having preference over subsequent lines; within the same line, the closer grade over the more remote; within the same grade, the male over the female, and in the same sex, the elder over the younger.
2. The Crown Prince, from his birth or from the time he acquires the claim, shall hold the title of Prince of Asturias and the other titles traditionally held by the heir to the Crown of Spain.
3. Should all the lines designated by law become extinct, the Cortes Generales shall provide for succession to the Crown in the manner most suitable to the interests of Spain.
4. Those persons with a right of succession to the throne who marry against the express prohibition of the King and the Cortes Generales, shall be excluded from succession to the Crown, as shall their descendants.
5. Abdications and renunciations and any doubt in fact or in law that may arise in connection with the succession to the Crown shall be settled by an organic act.

Section 58
The Queen consort, or the consort of the Queen, may not assume any constitutional functions, except in accordance with the provisions for the Regency.

Section 59
1. In the event of the King being under age, the King's father or mother or, in default thereof, the oldest relative of legal age who is nearest in succession to the Crown, according to the order established in the Constitution, shall immediately assume the office of Regent, which shall exercise during the King's minority.
2. If the King becomes unfit for the exercise of his authority, and this incapacity is recognized by the Cortes Generales, the Crown Prince shall immediately assume the Regency, if he is of age. If he is not, the procedure outlined in the foregoing paragraph shall apply until the coming of age of the Crown Prince.
3. If there is no person entitled to assume the Regency, it shall be appointed by the Cortes Generales and shall be composed of one, three or five persons.
4. In order to exercise the Regency, it is necessary to be Spaniard and legally of age.
5. The Regency shall be exercised by constitutional mandate, and always on behalf of the King.

Section 60
1. The guardian of the King during his minority shall be the person appointed in the will of the deceased King, provided that he or she is of age and Spaniard by birth. If a guardian has not been appointed, the father or the mother shall be guardian, as long as they remain widowed. In default thereof, the guardian shall be appointed by the Cortes Generales, but the offices of Regent and Guardian may not be held by the same person, except by the father, mother or direct ancestors of the King.
2. Exercise of the guardianship is also incompatible with the holding of any office or political representation.

Section 61
1. The King, on being proclaimed before the Cortes Generales, will swear to faithfully carry out his duties, to obey the Constitution and the laws and ensure that they are obeyed, and to respect the rights of citizens and the Self-governing Communities.
2. The Crown Prince, on coming of age, and the Regent or Regents, on assuming office, will swear the same oath as well as that of loyalty to the King.

Section 62
1. It is incumbent upon the King:

Section 63
1. The King accredits ambassadors and other diplomatic representatives. Foreign representatives in Spain are accredited before him.
2. It is incumbent upon the King to express the State's assent to international commitments through treaties, in conformity with the Constitution and the laws.
3. It is incumbent upon the King, following authorization by the Cortes Generales, to declare war and to make peace.

Section 64
1. The King's acts shall be countersigned by the President of the Government and, when appropriate, by the competent ministers. The nomination and appointment of the President of the Government and the dissolution provided for under section 99, shall be countersigned by the Speaker of the Congress.
2. The persons countersigning the King's acts shall be liable for them.

Section 65
1. The King receives an overall amount from the State Budget for the maintenance of his Family and Household and distributes it freely.
2. The King freely appoints and dismisses civil and military members of his Household.