Our story

CSE has a rich history of foreign signals intelligence (SIGINT) and communications security (COMSEC) going all the way back to the Second World War and the very beginning of Canadian SIGINT.

What began as a military signals corps in support of the British War effort quickly became a joint military and civilian operation. By the end of the war, the Canadian intelligence efforts had exceeded all expectations and demonstrated how effective and important these capabilities could be to the continued USA-Commonwealth partnership in the emerging post-war era. Established in 1946 the Communications Branch of the National Research Council (CBNRC), became Canada’s national cryptologic agency. In 1975, the CBNRC was renamed the Communications Security Establishment, under the Department of National Defence.

For 75 years, CSE has proved a valuable asset to the Government of Canada and to its allied partners, remaining committed to its primary mission: providing the federal government with foreign signals Intelligence vital to Canada’s National Security and protecting Government of Canada communications.

The Examination Unit and the JDU

Established in June 1941, the Examination Unit (XU) was Canada's first civilian office solely dedicated to decryption of communications signals. Until then, SIGINT was entirely within the purview of the military, and mostly limited to intercepts.

At the beginning of the Second World War, Canadian armed forces were already collecting encrypted signals from enemy military and foreign diplomatic communications traffic. Canadian military intercepts of enemy SIGINT were used mostly to locate German U-boat positions and movements, based on traffic analysis, which was shared with our British allies, and later, the Americans.

With the Nazi occupation of France, US military intelligence leaders encouraged Canada to put together a civilian office that would decrypt signals traffic, while the Canadian Army and Navy could continue to collect the raw SIGINT. In June 1941, the Examination Unit was established to begin decrypting enemy signals traffic, such as messages from the Vichy Government and other military and diplomatic communications. On occasion, depending on the type of communications, some cyphered intelligence could be analysed by the military, but it was the civilian XU that would regularly decipher content and disseminate intelligence to Canadian Foreign Affairs as well as to the Allies.

Within a few months of being set up, the XU had broken secret German communications codes with their operatives in South America, and acquired the complete key list, with which they were regularly able to read the encrypted German messages. Soon after Japan brought the United States into the War by attacking Pearl Harbor in December 1941, a Japanese Section was added to the XU.

By 1945, the disparate SIGINT collection units of the Navy, Army and Air Force were brought together in the Joint Discrimination Unit (JDU), which was headquartered in Ottawa in the same building as the XU. By the end of the war, the two Units, military JDU and civilian XU, were able to coordinate signals intelligence collection, analysis, and dissemination so efficiently that a case was made for the establishment of a peacetime Canadian cryptologic agency. In August 1946, the Communications Branch of the National Research Council of Canada (CBNRC), later to be renamed the Communications Security Establishment, was founded.

A testament to the value of the XU's contribution to the Allied War effort can be found in the secret Order in Council under which the postwar cryptologic agency was established as the CBNRC. Specifically, the creation of a peacetime civilian organization was recommended in order “to allow the individuals [of the XU and JDU] with highly developed and virtually irreplaceable skills and expertise to continue their work”.



SIGINT refers to the interception of signals that are often encrypted to protect the secrecy of the information they carry. Enciphering and deciphering information has been around as far back as recorded history, but the cryptologic history of signals is relatively new, beginning with the latter part of the industrial age.

The interception of signals and the protection of government telecommunications has been the Communications Security Establishment’s mission focus since its establishment in 1946 as the Communications Branch of the National Research Council of Canada (CBNRC).

The CBNRC was formed at the end of the Second World War by combining Canada’s two wartime offices; the civilian Examination Unit (XU) and the military Joint Discrimination Unit (JDU). Created through a secret Order in Council signed in April 1946, the CBNRC began operations on 3 September 1946. This new organization, which would later become CSE, included the former employees of the XU and JDU who came back to work together at their new jobs under the direction of former head of the JDU, Col. Edward Drake.

Their mission was to continue to make use of the expertise they had developed during the war, and to continue to support the close collaboration that had developed between Canada, the United States and the United Kingdom on the sharing of vital signals intelligence.

CBNRC becomes CSE

In 1974, CBC Television aired a documentary “The Fifth Estate: the Espionage Establishment.” While the program focused primarily on American international espionage, the program also included information on CBNRC – the first time the organization had ever been mentioned in public. The show’s description of signals intelligence collection and information sharing within the Five-Eyes partnership, caused a sensation, and led to the first ever acknowledgement of the existence of the CBNRC in Canada’s Parliament. The following year, 1975, the Communications Branch of the National Research Council was moved to the Department of National Defence and renamed the Communications Security Establishment (CSE).

The End of Cold War

The fall of the Berlin Wall in November 1989 and the official reunification of Germany one year later, in November 1990, precipitated the end of the Warsaw Pact, the military alliance between the Soviet Union and the Communist Bloc countries, in March 1991. The eventual collapse of the Soviet Union and the end of the Cold War, was not a surprise, but the speed with which it happened presented new challenges for the Five-Eyes partnership. CSE had to adapt tradecraft to identify new threats to Canada’s national security and stay ahead of shifting trends in telecommunications technologies.


December 24, 2001 – New legislative powers to CSE

The events of September 11, 2001 precipitated the ratification of Canada’s Anti-terrorism Act (ATA), which received Royal Assent on December 18, 2001. The ATA’s amendments to the National Defence Act formally acknowledged and mandated CSE’s activities. It also made amendments to the CSIS Act, the Criminal Code, and the Official Secrets Act, which became the Security of Information Act, allowing CSE to execute its mandate within the broader scope of the Canadian security and intelligence community and law enforcement.

2011 – CSE becomes a Standalone Agency

In November 2011, CSE reached another key milestone by being recognized as a stand-alone agency. CSE still operated under the National Defence Portfolio and was constrained by the National Defence Act, however, becoming a stand-alone agency allowed CSE to embrace increased responsibilities and accountability.

The Cyber Centre

The Canadian Centre for Cyber Security (Cyber Centre) was developed in response to the 2016 Cyber Review Consultations with Canadians, which identified key issues to address, including the need for clear points of accountability on cyber security, better coordination and collaboration between departments on cyber security issues, greater clarity on how and with whom the private sector should engage, and greater federal leadership on cyber security.

Following the allocation of funds in the February, 2018 Federal Budget, CSE, in collaboration with Public Safety Canada and Shared Services Canada, launched the Cyber Centre on October 1, 2018.

The Canadian Centre for Cyber Security leads the Government of Canada’s response to cyber security events. Working side-by-side with the private and public sectors, the Cyber Centre protects and defends the country’s valuable cyber assets and helps develop Canada’s cyber security talent.

2019 – CSE Act

The CSE Act, which came into force in August 2019, marked a milestone event for the Communications Security Establishment. Together with the Privacy Act, the Criminal Code, and the Canadian Charter of Rights and Freedoms, the CSE Act provides clear, explicit mandates to CSE.

Read more about the CSE Act.




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