54 U.S.C. § 312104

(a) Membership .— The affairs of the National Trust shall be under the general direction of a board of trustees composed as follows: (1) The Attorney General, the Secretary, and the Director of the National Gallery of Art, ex officio. (2) Not fewer than 6 general trustees who shall be citizens of the United States. (b) Designation of Another Officer .— The Attorney General and the Secretary, when it appears desirable in the interest of the conduct of the business of the Board and to such extent as they consider it advisable, may, by written notice to the National Trust, designate any officer of their respective departments to act for them in the discharge of their duties as a member of the Board. (c) General Trustees.— (1) Number and selection .— The number of general trustees shall be fixed by the Board and shall be chosen by the members of the National Trust from its members at any regular meeting of the National Trust. (2) Term of office .— The respective terms of office of the general trustees shall be as prescribed by the Board but in no case shall exceed a period of 5 years from the date of election. (3) Successor .— A successor to a general trustee shall be chosen in the same manner and shall have a term expiring 5 years from the date of the expiration of the term for which the predecessor was chosen, except that a successor chosen to fill a vacancy occurring prior to the expiration of a term shall be chosen only for the remainder of that term. (d) Chairman .— The chairman of the Board shall be elected by a majority vote of the members of the Board. (e) Compensation and Reimbursement .— No compensation shall be paid to the members of the Board for their services as such members, but they shall be reimbursed for travel and actual expenses necessarily incurred by them in attending board meetings and performing other official duties on behalf of the National Trust at the direction of the Board.