Dame Stella Rimington was a trailblazer in the world of intelligence on a number of fronts. She made history in 1992 as the first female director general of Britain’s Security Service MI5 and of any of the world’s leading intelligence agencies. Importantly, Stella was chosen on ability and not because MI5 thought it politically correct to appoint a woman as its head. Shockingly, she was not invited to apply for the post; there was no interview or selection panel. She only discovered her promotion to director after Prime Minister John Major had approved her appointment. She was not asked if she wanted the job.

She was also the first head of MI5 to be publicly named and photographed. This had unforeseen consequences because it brought unwanted attention from the media as every detail of her private life was aired in the newspapers. The London Evening Standard published an unattractive photograph of her and the Sun newspaper ran a sensationalist story under the headline ‘MI5 Wife in Secret Love Split’ about the separation from her husband. Her life that was once private and secret was thrown wide open, and it necessitated moving house to a secure, undisclosed location.

Her career had begun 25 years earlier in India, in 1967, after she was invited to work as an assistant to the First Secretary at the High Commission. Only after beginning the post did she discover that her husband was working undercover as an MI5 representative in India.

When they returned to London in 1969, Stella applied for a permanent post with the Security Service and was appointed junior assistant officer at a time when the men were recruited as officers and the women as assistant officers. There was in effect a separate, second-class career structure for women who carried out a wide range of support work, but not what Stella called ‘the sharp-end of intelligence gathering operations’, in a Guardian article in 2001 headed ‘Tinker, tailor, soldier, mum’.

Across a period of 25 years Stella gained experience in the three main areas of MI5’s work of counter-terrorism, counter-espionage, and counter-subversion. It led to her appointment as one of only two deputy directors in 1990 and one in which she oversaw the move to the agency’s current home at Thames House. In December the following year, she made a historic visit to Moscow to make the first friendly contact with her counterparts in Russian intelligence, the KGB. She believed very firmly in establishing a liaison with them in the same way as had been achieved with other countries in the Eastern bloc. That she was the emissary for this significant mission says something about her as a steely, composed character – a character which is said to have been the inspiration for the strong female figure of ‘M’, played by Dame Judi Dench in the James Bond films, from Goldeneye to Skyfall.

During her time as director, Stella was a catalyst for major change within MI5 in bringing about more openness with the public and overseeing the first release of its files into the National Archives at Kew. By this policy of openness, she began the modernisation of the service and contributed to the greater level of transparency that exists today. It was unthinkable when the worldwide web began to emerge that one day MI5 would have its own website and social media account on Instagram. Arguably, it may not have happened without Stella’s groundwork as director. Her appointment paved the way in 2002 for the second female head, Eliza Manningham-Buller.

The journey for women up to this point had been a long one. Even though a certain amount of sexism lingered on in the service after Stella’s appointment, MI5 had been recruiting a higher proportion of women at executive and officer level than any other branch of government. She followed in the footsteps of thousands of unnamed women who had quietly worked for British intelligence for decades, many as experts in their field in wartime, but who did not reach the top jobs. There were women in its history like Jane Sissmore (later Archer) and Milicent Bagot who became experts for MI5 in Communism and Soviet espionage. During the Cold War it appears that the women’s operational roles took a backward step and were limited to surveillance, and even then, acting as a camouflage or decoy for the male officer. Given the secrecy still surrounding MI5 it is hard to assess in any detail how women like Stella were beginning to rise in its ranks.

The Cold War dominated much of Stella’s career and it was one in which she did not let down her guard. A complacency had emerged in government after the fall of the Berlin Wall, the thaw in relations with Russia and the collapse of the Soviet Union. But Stella understood the hidden threats to the UK and spoke out in 1994 that the presence and activities of Russian intelligence officers was on the increase in the country at a time of supposedly good relations. Her time as director oversaw another primary threat to the mainland by the IRA. It was during her final year as director that two people were killed from a bomb planted by the IRA at London’s Canary Wharf.

In retirement, among other activities, Stella took up writing and in 2001 published her autobiography Open Secret. It is said that there is much she left out due to ongoing secrecy. She went on to pen a dozen crime novels, the majority about a female intelligence officer, Liz Carlyle, whose missions centre on the fight against terrorism. Always reticent in speaking about her own career, one wonders how much in the novels is autobiographical – she certainly had the operational experience that gives them their real-life ambience. They may be the closest to ever understanding the deeper levels of her own career. In 2014 she revealed in a BBC interview that her novels had been security cleared by MI5 and that some operational aspects and names had to be changed. Writing up to the end of her life, Stella’s final novel, The Hidden Hand, was published earlier this year.

Stella died on 3 August 2025 aged 90. Her career symbolises diversity in leadership and she will forever be remembered as the first woman to break through decades of barriers to liberate women to be able to achieve the highest levels in intelligence. As to the breadth of her own personal legacy within MI5, so much remains hidden by official secrecy, but we can say that she was the driving force and visionary who began the journey towards a more modern service. Today, it is a service that is willing and capable of adapting much more easily and swiftly to contemporary threats and one that is more comfortable in embracing diversity in its workplace at all levels.

Quite simply put, Dame Stella Rimington changed the history of MI5.