Defence Security and Vetting Service

The Defence Security Division (DSD) (formerly the Defence Security and Vetting Service (DSVS) and the Defence Security Authority (DSA)¹) is a security agency within the Australian Government, and plays a crucial role in maintaining national security.

The DSD sits within Australia’s National Intelligence Community (NIC) security architecture as Defence’s principal protective security authority. DSD is responsible for protective security, counterintelligence, and insider‑threat detection and mitigation within the Australian Defence Organisation.²

DSD also provides outreach security and cybersecurity services, the provision of security threat and risk assessments, and Security Intelligence (SYINT). DSD investigates major security breaches and manages the Defence Industry Security Program (DISP).³

DSD agents consist of SYINT analysts, physical security specialists, security investigators and Special Defence Security Officials.⁴ DSD agents are also embedded within the Australian Security Intelligence Organisation (ASIO) for closer collaboration on matters pertaining to Defence-specific espionage and Top Secret Privileged Access security clearances.⁵⁴ DSD is the parent agency of the Australian Government Security Vetting Agency (AGSVA).⁶⁷

DSD agents are accredited Australian Government investigators, consistent with their U.S DCSA Special Agent counterparts. DSD agents are required to complete the Diploma of Government (Security) and the Certificate IV in Government (Investigation) or the Diploma of Government (Investigation) through ASIO T4-Protective Security.⁸

The Chief Security Officer (CSO) is the primary counterintelligence official responsible for Defence security within the Australian Government and oversees the Defence Security Division. The current incumbent is First Assistant Secretary Ms Monique Hamilton PSM.⁹¹⁰

The CSO is an executive‑level organisational position, established under the Department of Defence’s internal governance framework and drawing its authority from the:

• Safeguarding Australia’s Military Secrets Act 2024¹¹
• Defence Act 1903 (general powers of the Secretary and CDF)
• Defence Legislation Amendment (Security of Defence Premises) Act 2011 (authorising the use of lethal force in the protection of Defence premises)¹²
• Public Service Act 1999 (APS employment and SES authority)
• Protective Security Policy Framework (PSPF)
• Defence Security Principles Framework (DSPF)

DSD agents specialise in a range of duties, including:²¹³

• Conducting covert field investigations into major national security breaches (including the theft of seven rocket launches in 2007 and thwarting the Holsworthy Barracks Terror Plot),¹⁴
• Providing protective security support and cooperation with ASIO and the Australian Federal Police (AFP) in the investigation of major security incidents, consistent with its role in assisting national security operations (see Operation PENDENNIS),¹⁵
• Conducting special offensive and defensive counterintelligence espionage activities (including identifying double-agents across Australian Government),
• Providing State-sanctioned cybersecurity and cyber-assurance operations in collaboration with the Australian Signals Directorate,
• Liaising with national and international intelligence, counterintelligence and security entities in the provision of government security,
• Administrating the Australian Government Security Vetting Agency,¹⁶
• Developing and governing security policy that complies with Australian Government protective security policy,
• Contributing to broader national security outcomes by managing the Defence Security Principles Framework, which helps decision-makers understand and manage evolving security risks effectively.¹⁶