David Smith completed Officer training at the Officer Cadet School of New Zealand (OCS (NZ)) on exchange from the Royal Military College-Duntroon in 1991. He graduated with the Sword of Honour in December that year into the Royal Australian Infantry Corps. During his career he has served as a Platoon Commander, Company Commander and Operations Officer in the 2nd Battalion, The Royal Australian Regiment (2RAR), Exchange Instructor at OCS (NZ), Aide-de-Camp to the Chief of Army and Brigade Major, 3rd Brigade.
From 2009-2010, David was Commanding Officer 2RAR and from May 2011-January 2012, he was Deputy Commander of the US led Combined Team-Uruzgan in Afghanistan. David has served on operations in East Timor, the Solomon Islands and Afghanistan. He was appointed a Member in the Military Division of the Order of Australia in June 2012 for his service as Commanding Officer 2RAR and awarded a United States Bronze Star Medal in April 2012, and the Distinguished Service Medal in January 2013 for his service in Afghanistan.