Canadian Prime Minister's Office

In Canada, the Office of the Prime Minister (more commonly referred to as the Prime Minister's Office and abbreviated as PMO), located in the Langevin Block, facing Parliament Hill, in Ottawa, is one of the most powerful parts of the government. It is made up of the prime minister and his or her top political staff, who are charged with advising the prime minister on decisions, making the office a wholly partisan body. It should not be confused with the Privy Council Office (PCO), which is the top office that controls the civil service and is expressly non-partisan. The PMO is concerned with making policy whereas the PCO is concerned with executing the policy decisions decided by the government.

In Canada, the Office of the Prime Minister is widely referred to as the "Prime Minister's Office" and although the latter rendering of the name is completely unofficial, the office's English abbreviation is always given as PMO as opposed to OPM. (In French, the PMO is known as le Cabinet du Premier Ministre and abbreviated as CPM, or often literally translated as le Bureau du Premier Ministre, abbreviated as BPM.) In addition, unlike examples such as 10 Downing Street, the White House and even Rideau Hall, the Canadian Prime Minister's official residence of 24 Sussex Drive is not widely used as a metonym for the Prime Minister's Office. This is because, unlike those examples, the Canadian Prime Minister's official residence is not the site of any bureaucratic functions.

One of the most important roles of the PMO is related to government appointments, which are made by the Queen-in-Council (or Governor-in-Council), but, as Canada is a constitutional monarchy, this is done on the normally binding advice of the prime minister. The PMO, thus, aids in finding suitable candidates for the prime minister to put forward to the monarch or viceroy for appointment to positions such as the governor general and lieutenant governors, senators, supreme court justices, chairpersons of ministerial boards, heads of Crown corporations, and more. The PMO also includes speech writers, strategists, and communications staffers who shape the prime minister's and Cabinet's message as well as keeping the prime minister informed on events that take place in government and across the country. They also act as a link between the political party organization and the government.

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