Col Bennett joined the NZDF Regular Force as a commissioned officer and Psychologist in 1987. She served for 20 years in a variety of operational, research and policy roles, more latterly as the Director of Military Personnel Policy and Director Strategic Human Resources. During this time she also held a number of representational roles including as the NZ National representative on the HUM Group of the Technical Cooperation Panel. She is a graduate of the NZDF Command and Staff College, holds Masters degrees in business and strategy, and in 2003 was made a Member of the NZ Order of Merit. She transferred to the Reserves in 2007 to work in broader government roles before returning to the Regular Force in December 2016 to take up the role of Chief Mental Health Officer in the Directorate of Health of the NZDF.