To amend the Defence Act, 1957, so as to insert four definitions and to amend two; to provide for the establishment of a Defence Secretariat; to provide for the appointment of a Secretary for Defence as head of the said Defence Secretariat; to determine the powers, duties and functions of the said Secretary for Defence; to further determine the powers, duties and functions of the Chief of the South African National Defence Force in the exercise of his military executive command of the South African National Defence Force; to repeal a certain obsolete provision; to amend the text; and to make further provision regarding the exemption of members of the South African National Defence Force from payment of tolls; to amend the Defence Amendment Act, 1967, so as to repeal a certain obsolete provision; and to provide for matters in connection therewith.