Introduction to the Security Service

MI5's mission is to keep the country safe. For more than a century we have worked to protect the UK from a range of threats, whether it be from terrorism or hostile activity by states.

Latest News

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MI5 Director General Ken McCallum has welcomed the National Security Act receiving royal assent.

Ken McCallum delivering Bowman lecture

Our director general, Ken McCallum, delivered the annual Bowman lecture at The University of Glasgow earlier this month.

Fact or Fiction

MI5 once used Wormwood Scrubs prison as our headquarters
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