The States Reorganisation Act,1956
Section 19. Staff of the Council
(1) Each Zonal Council shall have a secretarial staff consisting of a Secretary, a Joint Secretary and such other officers as the Chairman may consider necessary to appoint.
(2) The Chief Secretaries of the States represented in such Council shall each be the Secretary of the Council by rotation and hold office for a period of one year at a time.
(3) The Joint Secretary of the Council shall be chosen from amongst officers not in the service of any of the States represented in the Council and shall be appointed by the Chairman.