Captain Munro graduated from the Royal Military College on 13 December 1967, and was allotted to the Royal New Zealand Signal Corps. He arrived in Vietnam on 10 November 1970, on a posting to General Staff (Intelligence) Section Headquarters, First Australian Task Force based in Nui Dat.
From November 1970 to May 1971, Captain Munro was responsible for compiling the enemy order-of-battle which involved detailed and continuous analysis of enemy unit organisations and capabilities. In June 1971 he took over the duties of General Staff Officer Grade Three (Intelligence).
In this role he was responsible for the synthesis and dissemination of the intelligence reports which were received each day, alerting and directing interrogation teams, ensuring that aerial reconnaissance pilots were briefed daily on the current situation, and for conducting briefings for many visitors and unit commanders.
These tasks necessitated long hours of work which Captain Munro accepted without complaint. He applied himself diligently throughout his tour of duty to help ensure that timely and reliably based intelligence was passed to units and to the staff.
His dedication and persistence were an example to all those who worked with him and reflected great credit upon himself, his Corps and the New Zealand Army.