In June 1985 she was promoted to squadron leader,[3] and became Sub-Section Head in the Aircraft Equipment Engineering Division (AEENG3) of Headquarters Support Command at Victoria Barracks, Melbourne.
5 Advanced Systems Engineering Course at RAF Cranwell, she became a liaison officer in the Directorate of Scientific and Technical Intelligence at the Ministry of Defence in London.
[3] Returning to Canberra in 1996, she took the role of Project Director of Joint Project 2030 (JP2030), the Australian Defence Force's Joint Command Support Environment (JCSE), in the Command and Support Systems Branch of the Defence Acquisition Organisation (DAO).
[6] She completed a Graduate Diploma in Strategic Studies at the Joint Services Staff College, and became the first woman in the RAAF to become a member of the General List when she was promoted to group captain in 1996.
[3] When she was subsequently promoted to air vice marshal in 2003, she became the first woman to attain two-star rank in the ADF.
[8] She assumed duties as Director General Information Services, responsible for the operations and support of Defence's fixed communications networks and computer systems throughout Australia.
[12] Hammer has been married to fellow RAAF officer, Air Vice Marshal David Dunlop, since September 2000.