MI6 rated Europe’s most effective intelligence agency

Britain’s MI6 has been rated Europe’s leading foreign intelligence service by intelligence professionals from across the Western alliance, according to a survey that placed the Secret Intelligence Service well ahead of its continental counterparts.

The assessment, published by the French magazine L’Express, drew on the views of 60 serving and former intelligence officials from 25 countries. Over three months, the publication canvassed members of allied intelligence communities to rank the effectiveness of their opposite numbers, producing a rare peer assessment of Europe’s principal espionage agencies.

France’s General Directorate for External Security (DGSE) secured second place, earning praise for its global reach and ability to conduct sophisticated covert operations. The Netherlands’ AIVD/MIVD completed the top three, while Slovakia’s intelligence service was rated the weakest among those surveyed.

Respondents overwhelmingly placed MI6, formally known as the Secret Intelligence Service, at the top of the rankings, citing its ability to recruit high-level agents and penetrate the political and security establishments of hostile states, including Russia, China, Iran and Turkey. Intelligence officers also highlighted the agency’s reputation for patiently cultivating sources over many years, allowing it to build long-term access to valuable intelligence.

“The United Kingdom has by far the strongest secret services in Europe. MI6 is extraordinary,” Robert Gorelick, a former CIA station chief, told L’Express. A former director of France’s DGSE said British intelligence officers had mastered “the long game”, investing in agents over a decade or more, much like their Russian counterparts, while also displaying a willingness to employ imaginative covert methods.

Olivier Mas, a former senior DGSE officer, attributed Britain’s intelligence tradition to its centuries-long experience as a global power. He argued that the country’s imperial past, together with its strategic rivalry with Tsarist Russia during the 19th-century “Great Game” in Central Asia, helped shape an intelligence culture that continues to influence MI6 today. Britain’s ability to recruit graduates from Oxford and Cambridge was also cited as one of its enduring advantages.

The survey also highlighted Britain’s role in the war in Ukraine. British intelligence was among the first to warn publicly that Russia was preparing a full-scale invasion, assessments that were later borne out by events. Since then, MI6 has remained closely involved in supporting Kyiv alongside its allies. Ralph Goff, the CIA’s former chief of operations for Europe and Eurasia, said Britain had taken the lead on intelligence relating to Ukraine, with the United States working in close partnership.

Britain finished the survey with 251 points, comfortably ahead of France’s DGSE on 169. Although the French service attracted only five first-place votes, respondents praised its ability to combine technical intelligence, human intelligence and covert action on a global scale. One Polish intelligence official described it as the only continental European service with a truly worldwide operational reach.

Europe’s leading intelligence services

While MI6 emerged as the clear leader, the survey reflected growing respect for France’s external intelligence service, particularly for its operations in Africa and the Middle East, where Paris has long maintained military and diplomatic influence. Intelligence professionals also commended the Dutch services for consistently delivering high-quality intelligence despite their comparatively modest size, placing them ahead of several much larger agencies. The findings suggest that, in the view of many of Europe’s intelligence professionals, MI6 remains the benchmark against which other foreign intelligence services are measured.