Terry OLeary worked at Garden Island Dockyard as Technical Officer Electronics & Communications in 1970s, then Hardware Engineer in IT industry and then Laboratory Manager. Served 6 years Army Reserve in 1970s & 1980s. Completed part time Applied Science Degree followed by Master of Applied Science.

Moved to Canberra in 1990 to work in Defence as an Analyst. Then worked as Senior Professional Officer for DSTO in Navy Office. Attended Joint Services Staff College and completed Master Degree at ADFA UNSW Campus in Management. Worked in Defence Project Managment and left Defence to teach at Canberra Institute of Technology till retirement.