Patrick Graham Millen KSG QSO JP (5 August 1927 – 14 July 1994) was a diplomat and the New Zealand Secretary of the Cabinet and Clerk of the Executive Council from 1973 until 1987.

[3] Born in Beirut, Lebanon, the son of a Scottish Banker, he had a cosmopolitan upbringing where he lived in Baghdad and Singapore and was educated in England, India, Ceylon.

He left the Royal Marines to attend Oxford University's Pembroke College, eventually gaining a Masters in philosophy, politics, and economics.

After Kirk's death in office, the caucus voted in Bill Rowling as Prime Minister and he inherited a very challenging environment where the Labour policies no longer accorded with the impact of the oil shock.

While Millen disagreed with many of his policy positions, he kept his reservations to himself and did not seek to influence Cabinet decisions which included the abandoning of the Labour parties New Zealand Superannuation Scheme.

Occasionally he would pause in his note taking and put his hands flat on the table to indicate that he was not recording what could be vigorous discussions in order not to inhibit the debate.

[6][7] As a staunch believer in Westminster parliamentary democracy in 1979 he published the Cabinet Office Manual which outlines the main laws, rules and constitutional conventions affecting the operation of the New Zealand Government.

[8] This was a document first mooted by Sir Sidney Holland some 30 years prior when Millen's predecessor Foss Shanahan reorganised the processes for Cabinet operation.

He was a key member of the Danks Committee on Official Information which led to the introduction of an Act in 1982 that reversed the presumption of secrecy in the operations of Government.

[17] Following retirement from the public service in 1987 he became advisor to the National Director of IHC, secretary on the Committee of Advertising Practise, and a member of the Wellington Criminal Justice Advisory Council.