Parliamentary Private Secretary to the Prime Minister Bonar Law's Parliamentary Private Secretary, J.C.C. Davidson acted in effect as his Chief of Staff. Margaret Thatcher's downfall from the Conservative Party leadership in 1990 is attributed by many to the actions of her Parliamentary Private Secretary, Peter Morrison, in failing accurately to count votes amongst Conservative backbenchers. Some Parliamentary Private Secretaries to the Prime Minister go on to hold higher office; Lord Dunglass served as Parliamentary Private Secretary under Neville Chamberlain and later went on to serve as Prime Minister in his own right. There can be multiple Parliamentary Private Secretaries to the Prime Minister at a given time.
Chief of Staff to the Prime Minister (Canada) Chief of Staff to the Prime Minister (Canada) The Chief of Staff of Canada's Prime Minister's Office is the top official of the office. The position was created in 1987 to head the PMO. Prior to the creation of the chief of staff position, the office was headed by the Prime Minister's Principal Secretary, a position which is now secondary to the chief of staff. People who held the position of principal secretary prior to 1987 were essentially "de facto" chiefs of staff, and may sometimes be informally referred to as chiefs of staff in some sources, but did not