The Defence Security Division (DSD) (formerly the Defence Security and Vetting Service (DSVS) and the Defence Security Authority (DSA)Inspector General of Intelligence & Security, Report into the Defence Security Authority 2011) 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.
DSD is composed of four specialised branches:
Special Activities Deployment Group (SAD Group), which deploys and serves as DSD’s covert operations and special missions arm; it conducts clandestine intelligence collection, sensitive security operations, and specialised technical activities requiring deniable capability Security Threat Assessments Branch (STAB), which provides strategic assessments of foreign intelligence risks, emerging security threats, and insider‑risk indicators affecting Defence personnel and facilities. Defence Industry Security Bureau (DISB), which oversees protective security policy, accreditation, and compliance for Defence industry partners, including the management of classified contract security requirements. Australian Government Security Vetting Agency (AGSVA), which is responsible for conducting personnel security vetting across Defence and other Commonwealth agencies, operating under DSD’s governance framework and policy oversight.
DSD agents are security and threat analysts, physical security specialists, and security investigators. DSD also employ Special Defence Security Officials (SDSOs), who serve as its designated special agents and hold distinct statutory authorities.
DSD special agents are unique within the Commonwealth in that they are the only officers authorised to exercise statutory use‑of‑force powers, including lethal force, while operating in plain clothes without displaying any Australian Government insignia. No other state or federal government role provides use‑of‑force authorities to officials who do not wear a uniform or some form of visible identification.
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. DSD is the parent agency of the Australian Government Security Vetting Agency.
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.
Chief Security Officer & First Assistant Secretary, Defence Security The Chief Security Officer (CSO) is the Australian Government's most senior counterintelligence officer, responsible for enterprise‑wide security across the ADO and head of the Defence Security Division. The CSO incumbent is also the 'First Assistant Secretary for Defence Security' (FAS-DS) within the Department of Defence.
The role is distinct from the Director‑General of Security, who leads ASIO and serves as Australia’s most senior national security officer. The current CSO is First Assistant Secretary Monique Hamilton PSM.
drawing its authority from the:
Safeguarding Australia’s Military Secrets Act 2024 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) Public Service Act 1999 (APS employment and SES authority) Protective Security Policy Framework (PSPF) Defence Security Principles Framework (DSPF)
Functions
DSD agents specialise in a range of duties, including:Security | Sectors | DefenceSecurity clearances – Vetting assessment Australian Government Security and Vetting Agency
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),Ex-bikie granted immunity in rocket launcher case now facing deportation after drug bust (smh.com.au) 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), 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, 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.Defence Industry Security Program - Australian Defence Organisation
See also Australian Secret Intelligence Service Australian Security Intelligence Organisation Australian Signals Directorate Australian Federal Police Holsworthy Barracks terror plot U.S Defense Counterintelligence and Security Agency Direction de la Protection et de la Sécurité de la Défense
References
External links Defence Security Division Official site. Open Australia Search: Parliamentary records mentioning 'Defence Security Authority'.