Barbados

(1) There shall be a President who shall be the Head of State.
... (Sec. 28)

A person is qualified to be nominated for election as President if he is a citizen of Barbados by birth or descent. (Sec. 29)

(1) Whenever the office of President is vacant, or if the term of office of the President is due to expire within not more than ninety days, the Prime Minister shall consult with the Leader of the Opposition with a view to their joint nomination of a candidate for election as President.
(2) If the Prime Minister and the Leader of the Opposition make in writing to the Speaker a joint nomination of a qualified candidate for election as President, being a nomination to which that candidate has consented, the Speaker shall notify both Houses of the joint nomination and, at a joint meeting of both Houses, shall ask the members whether any member has an objection to the candidate being declared duly elected, if no member objects thereto, the Speaker shall declare the candidate duly elected.
(3) If there is an objection under subsection (2) the Speaker shall not declare the candidate duly elected but shall suspend the joint meeting.
(4) The members of each House shall, immediately following the suspension, resume in their respective House and the presiding officer of each House shall put the question referred to in subsection (2) to a vote.
(5) Immediately upon announcing the result of the vote in each House, the joint sitting shall resume and the President of the Senate and the Speaker shall each announce the result of the vote.
(6) If the candidate receives not less than two-thirds of the votes cast in each House, the Speaker shall then declare the candidate duly elected.
... (Sec. 32)

(1) The executive authority of Barbados is vested in the President.
(2) Subject to the provisions of this Constitution, the executive authority of Barbados may be exercised by the President either directly or through officers subordinate to him.
... (Sec. 63)

(1) Whenever the President has occasion to appoint a Prime Minister he shall, acting in his discretion, appoint the member of the House of Assembly who, in his judgment, is best able to command the confidence of a majority of the members of that House.
(2) The other Ministers shall be appointed by the President, acting in accordance with the advice of the Prime Minister, from among the members of the two Houses.
… (Sec. 65)

There shall be a Parliament of Barbados which shall consist of the President, a Senate and a House of Assembly. (Sec. 35)

(1) The Senate shall consist of twenty-one persons who, being qualified for appointment as Senators in accordance with the provisions of this Constitution, have been so appointed in accordance with the provisions of this section.
(2) Twelve Senators shall be appointed by the President, acting in accordance with the advice of the Prime Minister, by instrument under the Public Seal.
(3) Two Senators shall be appointed by the President, acting in accordance with the advice of the Leader of the Opposition, by instrument under the Public Seal.
(4) Seven Senators shall be appointed by the President, acting in his discretion, by instrument under the Public Seal, to represent religious, economic or social interests or such other interests as the President considers ought to be represented:
Provided that before appointing any person under this subsection the President shall consult such persons as, in his discretion, he considers can speak for those interests and ought to be consulted. (Sec. 36) 

Subject to the provisions of section 38, any person who at the date of his appointment is a citizen of Barbados of the age of twenty-one years or upwards shall be qualified to be appointed as a Senator. (Sec. 37)

(1) The House of Assembly shall consist of thirty members or such greater number of members as Parliament may prescribe.
(2) The members of the House (who shall be known as “Members of Parliament”) shall be persons who, being qualified for election as such in accordance with the provisions of this Constitution, have been so elected in the manner provided by this Constitution. (Sec. 41)