Principal Private Secretary to the Prime Minister

The Principal Private Secretary to the Prime Minister is a senior official in the British Civil Service who acts as Principal Private Secretary to the Prime Minister of the United Kingdom. The holder of this office is traditionally the head of the Prime Minister's Office. In the Civil Service, the role is currently graded as a Director-General. To date, no woman has ever occupied the office. In fiction, the character of Bernard Woolley in the television series Yes, Prime Minister, occupied this post.

During Tony Blair's administration, he modified the law under which the Civil Service operated to create the role of Downing Street Chief of Staff, which though held by a political advisor outranked the Principal Private Secretary. When Gordon Brown ascended to office, he reversed the change to the Civil Service law. When David Cameron became Prime Minister, he promoted the then-PPS to a new post of "Permanent Secretary, Downing Street", a position which took over heading the Prime Minister's Office. In 2012, the postholder, Jeremy Heywood, was appointed as Cabinet Secretary, this post ceased to exist, and the role of Civil Service head of the Office reverted to the Principal Private Secretary.

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