Having been an officer of the Security Service for 33 years, Dame Eliza Manningham-Buller has tendered her resignation to Home Secretary John Reid.

In an official statement, the director general of MI5 said that she “has been privileged to lead the Security Service” during an era when it has faced and continues to confront two huge challenges, namely “a very serious threat [posed to the nation by terrorism] and “the need to grow and change at a rapid rate to tackle that threat”.

A true security professional brimming with intellectual drive, Dame Eliza assumed overall responsibility for counter-terrorism operations little more than a year after 9/11. To her enormous credit, this 58-year-old English graduate of Lady Margaret Hall, Oxford has since overseen a massive (and very positive) transformation of MI5 as the second female following Stella Rimington to lead the Service.

Of late, she has created a culture wherein the organisation is now far more approachable, instigating a dedicated web site and even recruiting agents and security managers through advertisements in national newspapers and security journals (witness of last month’s SMT).

In addition, the bold decision was taken to openly publish terror risk assessments for the very first time, while Dame Eliza who agreed her resignation date of April this year with Charles Clarke before he left office has maintained a high profile in the fight against terrorism that has been as much welcomed as it was unprecedented.

Only recently, Dame Eliza revealed that the Security Service knows about (and has been keeping tabs on) 30 separate plots by extremists, and had identified 1,600 individuals suspected of actively plotting (or facilitating) acts of terrorism on home shores and overseas. Knowing that the Security Service is really on top of its game is hugely reassuring to members of the public, the security profession and the police service. More importantly, perhaps, it also acts as a deterrent to would-be terrorist and criminal factions.

Above all, Dame Eliza Manningham-Buller has dedicated herself to the protection of this nation and its people. The contribution made to the security and safety of us all by a woman imbued with so much character and drive will, in time, be recognised as invaluable.

Whomever John Reid appoints as her successor early in the New Year, Dame Eliza will be a tough act to follow.

Brian Sims Editor