During the 1960s and early 1970s, civic action projects were undertaken on an increasing scale by the US, Australia and other countries of the Free World Military Forces throughout South Vietnam.

[1] According to Barry Smith civic action was not primarily motivated by altruism, but rather the political imperative of winning the support of the South Vietnamese people for the central government in Saigon.

[2] When the 1st Australian Task Force (1 ATF) first arrived in Phuoc Tuy Province in mid-1966, the military security situation was poor.

[6] Members of the 1st Battalion, Royal Australian Regiment (1 RAR) had conducted civic action projects while deployed in Bien Hoa Province in 1965.

[8] Consequently, four warrant officers from the Australian Army Training Team Vietnam (AATTV) were attached to 1 ATF under Captain Bob Rooney in May 1966, and the small group began carrying out civic action-type projects to assist the local population in Phuoc Tuy Province.

[12][Note 1] Despite these measures the Australian civic action program remained ad hoc, and was found difficult to sustain due to the other operational demands placed on 1 ATF.

[13] The 1st Australian Civil Affairs Unit (1 ACAU) was raised at Middle Head in Sydney on 10 April 1967[14] with an establishment of ten officers and 39 other ranks.

[15] Under the command of Lieutenant Colonel John McDonagh, Royal Australian Engineers (RAE), in June 1967 it moved to Nui Dat in Phuoc Tuy Province, South Vietnam.

It was also involved in providing aid to the local population when they were affected by the fighting, for instance in the aftermath of the Battle of Binh Ba in June 1969 when much of the village was heavily damaged.

In the final years of 1 ATF's deployment (1969–71), the unit was more independent, primarily undertaking its own programs to assist the villages and South Vietnamese administration.

By 1969, MEDCAPS were incorporated into Integrated Civil Action Programs (ICAPS), which were conducted by medical and other teams that would deploy overnight to a village and treat anyone who requested assistance.

In early 1969, the North Vietnamese authorities placed a price on the head of the then commander of the CAU, Lieutenant Colonel Kevin Latchford, suggesting their concern about the positive impact the unit was having on the local population.

During 1969–70, when 1 ACAU was under the command of Lieutenant Colonel Peter Gration, the Education Detachment also became responsible for youth and sports activities in Phuoc Tuy Province.

[23] The Liaison Detachment consisted of Vietnamese-speaking Australian officers trained at the RAAF School of Languages in Point Cook, Victoria.

Described by Gration as "the eyes and ears" of 1 ACAU, the Liaison Officers (LOs) were responsible for interacting with the civilian population on a daily basis, assessing where projects might be warranted, preparing feasibility studies, and developing close contacts at village level.

[19][24] Due to the nature of their work 1 ACAU personnel were quite vulnerable to enemy action and potentially could have suffered heavy casualties if the VC had decided to target them.

[30] Following their participation in the 1987 Welcome Home Parade in Sydney, former 1 ACAU members formed the 1st Australian Civil Affairs Unit Association on 10 April 1988.