Marc Ablong PSM was appointed Deputy Secretary at the Department of Home Affairs on 11 October 2018. Prior to this appointment, Marc filled the position of First Assistant Secretary Strategy and Capability, Department of Home Affairs, on secondment from the Department of Defence.

As at 1 July 2020, Marc will lead a realigned National Resilience and Cyber Security (NRC) Group responsible for Critical Infrastructure, Identity and Biometrics, Digital, Cyber and Technology Policy, Intelligence, International, Operation Sovereign Borders (OSB) Joint Agency Task Force (JATF) and Emergency Management Australia. NRC Group will be responsible for ensuring Australia's industrial base, nationally significant systems and critical infrastructure are more secure and resilient to a rapidly changing environment.  The Group will work to deliver economic benefit to the nation by enabling Australia to be more resilient, more secure, and better able to manage and recover from threats, hazards and crises.  

Marc spent 25 years in the Department of Defence in a range of positions across strategic policy & intelligence, capital equipment and acquisition policy, international policy, military strategy, maritime capability development, Air Force long-range planning, national support, information strategy and futures, strategic reform, and ministerial and executive coordination and communications.

In 2014, Marc was appointed First Assistant Secretary White Paper, to lead the development of the 2016 Defence White Paper, Integrated Investment Program and Defence Industry Policy Statement, which were released by the Government on 25 February 2016.  Following the release of the 2016 Defence White Paper, Marc was appointed as the inaugural First Assistant Secretary Contestability. Marc subsequently held roles as First Assistant Secretary Naval Shipbuilding Taskforce and First Assistant Secretary Defence Industry Policy (which he undertook concurrently with his role as leading the Naval Shipbuilding Taskforce). From October 2017 to April 2018, Marc acted as the Deputy Secretary Strategic Policy & Intelligence.

Marc has attended the Joint Services Staff College, the Centre for Defence and Strategic Studies and completed the Advanced Management Program 190 at the Harvard Business School. Marc was awarded the Public Service Medal in the Australia Day Honours 2018.