A recent peer review conducted among intelligence professionals across Europe ranks the United Kingdom’s Secret Intelligence Service (MI6) as the continent’s most powerful foreign intelligence agency. The survey involved 60 experts from 25 countries who assessed the operational capabilities and global reach of various agencies.
MI6 was lauded primarily for its expertise in recruiting high-level informants and infiltrating the ruling elites of countries including Russia, China, Iran, and Turkey. Former CIA station chief Robert Gorelick described MI6 as “extraordinary,” highlighting its leading edge among European services. According to a former head of France’s General Directorate for External Security (DGSE), MI6 distinguishes itself through long-term source cultivation, some spanning a decade, and a willingness to engage in covert “dirty tricks.”
The British service’s prominence is often linked to its historical legacy. Olivier Mas, a senior DGSE official until 2017, attributed MI6’s strength to Britain’s colonial past and its 19th-century rivalry with Tsarist Russia, known as the Great Game. He noted the agency’s recruitment of top talent from elite universities such as Cambridge and Oxford as a significant asset.
The review also emphasized MI6’s key role in providing early warnings about Russia’s likely invasion of Ukraine, a contribution that has been critical for Kyiv’s defense efforts. Ralph Goff, a former CIA chief of operations for Europe and Eurasia, remarked that the British “are in the lead on the Ukrainian file,” with other Western agencies closely following their lead.
France’s DGSE earned second place with 169 points, recognized for its near-global operational reach. The service combines technical intelligence gathering, human intelligence, and clandestine operational action. A Polish intelligence official noted that DGSE is the only continental European service with such extensive capabilities. The DGSE’s clandestine “action” arm, a military organization, has been credited with numerous lethal operations targeting individuals deemed threats to French security. Former French President François Hollande publicly acknowledged ordering at least 40 targeted killings of high-value jihadi figures in the Middle East and Africa during his tenure.
In third place, the Dutch General Intelligence and Security Service (AIVD) scored 97 points and earned praise for its effective use of resources and consistent operational success. Jorge Silva Carvalho, a former Portuguese intelligence director, called the AIVD “the best return on investment,” citing its unblemished track record.
The Ukrainian intelligence service was ranked fourth, noted for its innovation, resourcefulness, and willingness to take risks amid ongoing conflict. Germany’s Federal Intelligence Service (BND) ranked fifth; while often criticized as bureaucratic, it maintains a strong reputation for analytical expertise on global issues, though its espionage capabilities were viewed as less effective compared to its European peers.
At the lower end of the ranking, Slovakia’s intelligence service was regarded as the weakest among European counterparts. The study’s findings offer a rare glimpse into the competitive landscape of Western intelligence agencies based on direct assessments from insiders.