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.
Prime minister when Northern Ireland was a Majority Rule Parliament the head of government would be known as the Prime Minister of Northern Ireland. In Pakistan, the prime minister is referred to as "Wazir-e-Azam", meaning "Grand Vizier". The Prime Minister's executive office is usually called the Office of the Prime Minister in the case of the Canada and other Commonwealth countries, it is called Cabinet Office in United Kingdom. Some Prime Minister's office do include the role of Cabinet. In other countries, it is called the Prime Minister's Department or the Department of the Prime Minister and Cabinet as for Australia. In