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.

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MI5, SIS and GCHQ publish pay gap reports

Five Eyes conference at Stanford University

The heads of the Five Eyes domestic intelligence agencies today launched new advice to help organisations protect...

Fact or Fiction

There is an underground tunnel linking MI5 and SIS
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