According to O'Neill: "The First Battalion was in the final stages of its preparations for departure to Vietnam, and so the Fifth came in for more than its usual share of routine chores and administrative duties.

In March 1966 the battalion emplaned at Aero Paddock at Holsworthy and moved to Gospers for its final exercise, which included advances to contact, night movement, and defensive operations.

Many of the villagers did not support the VC due to the heavy taxes they levied, the manner in which they restricted civilian travel to the various markets for trade and because they conscripted those of military age.

This resulted in cordon and search operations of Duc My, Binh Ba, Ngai Giao, Phuoc Hoa, Xuyen Moc and on Long Sơn Island.

5 RAR had laid a sturdy platform for future battalions due to their innovative use of tactics, hard training, the professionalism with which they carried out their tasks and the subsequent respect won from the Vietnamese people'.

After shaking out for two weeks, the battalion began a reconnaissance in force in the northern and eastern parts of the rugged Nui Dinh mountain complex on 1 March 1969 – Operations Quintus Thrust I and II.

Towards the end of the tour, elements of the battalion also contributed to the pacification process through the construction of schools and housing and through the provision of medical and dental support to such villages as Ong Trinh and Phuoc Le'.

Special training was conducted, all vehicle floors were sandbagged, flak jackets and helmets worn whenever possible, and mine detectors used by all patrols.

The action began at 08:10 hours on 6 June when a Centurion tank and armoured recovery vehicle moving to a fire support base manned by 6 RAR was fired on by a rocket propelled grenade (RPG) from one of the houses in the village, located about 3 miles (4.8 km) north of the Australian Task Force base at Nui Dat.

By 14:00 hours D Company formed up west of the village and began a second sweep, with infantry leading and the tanks and APCs close behind.

A difficult combined arms clearance supported by Bushranger helicopter gunships and artillery then took place against determined opposition of the 1st Battalion of the PAVN 33rd Regiment.

[11][Notes 1] Following Australia's withdrawal of military forces from Vietnam in 1972 the government of the day decided that it would not sustain nine battalions of regular infantry.

[13] In 2006 the Australian Government announced that it would expand the Army to meet operational commitments, this time from six to eight regular infantry battalions.

[14] The invasion of Iraq in 2003 saw not only the overthrow of Saddam Hussein's Ba'athist regime by coalition forces in a three-week campaign but also the beginning of a violent insurgency and, in time, a Sunni-Shia civil war and widespread communal violence.

Initially known as the Al Muthanna Task Group (AMTG) this combined arms organisation was officially tasked with providing security to the Japanese Iraq Reconstruction Support Group (JIRSG) undertaking humanitarian assistance and conducting construction work in Al Muthanna.

[16] D Company, 5/7 RAR (Combat Team Tiger) was part of the fourth battle group rotation to Iraq (OBG(W) 2) led by 2nd Cavalry Regiment and commenced its six-month tour in late 2006.

[19] The complex nature of the environment in Iraq in 2006–07 as part of 'the Surge' resulted in a wide range of security, stability and counter-insurgency operations conducted under difficult conditions.

Soldiers patrolled extensively by day and night as a part of framework operations, set ambushes ('counter improvised explosive device patrols' in the politically correct terminology of the time) to retain freedom of action astride the approaches to Tallil and coalition lines of communication northwards to Baghdad, and sought to disrupt the indirect fire threat to the Coalition FOB.

The 5 RAR Battle Group regularly provided support to strike operations undertaken by United States Special Forces, including a mission late 2007 that resulted in the detention of a Corps-level high-value target.

During both tours members of 5 RAR trained and mentored the Iraqi Army and Police, as well as undertaking construction and reconstruction work to shape the operating environment.

The deployment also marked the first time that a mortar section from the battalion fired high explosive rounds to support friendly troops in contact since the Vietnam War.

The 5 RAR battle group was one of two units that made up the main fighting force of what was effectively a small coalition brigade called Combined Team Uruzgan (CTU).

Mentoring the Afghan National Army personnel of the 4th Brigade, 205th Hero Corps was an important part of the 5 RAR battle group's mission.

Together with their Afghan partners the 5 RAR battle group achieved relatively good success against the insurgents in Uruzgan in a range of deliberate clearances, strike operations, and framework activities that resulted in the recovery or capture of weapons, ammunition, enemy combatants, and the like.

Perhaps most importantly, these operations assisted the Afghans to exert influence in areas where the army or police presence had been contested or where it had not previously existed.

[23] Sapper Jamie Larcombe, an engineer from the 1 CER attached to Support Squadron, was killed by small arms fire on 19 February 2011 (along with an Afghan interpreter, Amiri).

5 RAR completed its mission as the mounting unit of MTF-2 in June 2011, handing over to MTF-3, a battle group led by 2nd Battalion, Royal Australian Regiment.

[25] Queen's and Regimental Colours were first presented to the 5th Battalion whilst it was at Tobruk Lines, Holsworthy on 29 October 1967, by the then Governor of New South Wales, Sir Roden Cutler, VC, KCMG, CBE.

Consequently, on 14 April 2007, the 5th Battalion created a small footnote in Australian military history by being the first unit to rededicate itself to its original colours in a sunset ceremony on a hilltop at Cultana Training Area, South Australia.

[29] Although much loved, the original colours were in need of replacement, so following the battalion's return from Iraq, new Queens' and regimental colours were presented to the unit by Mr Thomas Pauling, QC, the administrator of the Northern Territory, in a ceremony conducted at historical East Point, Darwin, on 5 June 2008 (the eve of the anniversary of the Battle of Binh Ba).