On 16 March 1949, the Australian prime minister, Ben Chifley, issued a Directive for the Establishment and Maintenance of a Security Service, appointing South Australian Supreme Court Justice Geoffrey Reed as the first Director-General of Security. The need for an Australian security service (to be modelled on the United Kingdom Security Service, MI5) became apparent with the United States administration of the day expressing disaffection with the state of security in Australia, particularly in counter-intelligence.
Justice Reed advised the Prime Minister in August 1949 that he had decided to christen the service the Australian Security Intelligence Organisation (ASIO).
Expansion and revision
On 6 July 1950 Prime Minister Robert Menzies issued an expanded and more specific Directive titled Charter of the Australian Security Intelligence Organization on the appointment of Colonel Charles Spry as the new Director-General of Security.
Both the Establishment and Charter Directives have been now largely superseded by federal legislation, notably by the Australian Security Intelligence Organisation Act 1979.