In March 1966 the Prime Minister, Harold Holt, announced that the battalion group deployed to Vietnam would be expanded to a two-battalion task force. The RAAF commitment to support the task Force was to be increased, and hence the headquarters of the Australian Army Force Vietnam was to become the joint Services headquarters of Australian Force Vietnam. Since the COMAFV was a joint Service commander, he became responsible not to the CGS but to the COSC through its Chairman, Lieutenant General Wilton.

The COMAFV was the Australian national commander with responsibility for the administration of the Australian forces in Vietnam. He had no responsibility for the operational employment of the Australian forces, primarily the Task Force in Phuoc Tuy Province, which came under the command of a US corps commander, but he was consulted on major operational matters, such as the decision in early 1968 to deploy the Task Force into Bien Hoa Province. The COMAFVs were given little political or strategic direction from Canberra and often had to make decisions according to what they thought would have been acceptable in Canberra.^[10]

The appointment of COMAFV set a precedent for later ADF operations. The government realised that, for overseas operations, there was great value in appointing a national commander who could ensure that Australian policy was followed. Further, if more than one Service was deployed, there was advantage in having one national joint Service commander deal with allied commanders-in-chief and host governments.