All about Robert Hannigan

Robert Hannigan to step down as GCHQ chief

Kate hails GCHQ puzzle book in aid of Heads Together mental health campaign

GCHQ boss 'sorry' for historic treatment of gays including Alan Turing

National Cyber Security Centre 'to combat threats that exist online'

GCHQ chief urges Government action over data encryption

It's give us a clue GCHQ, with only hours to solve crypto-challenge