Practically, the tenets of responsible government require the sovereign or his viceroy, the governor general, to almost always follow only that advice tendered by the Cabinet: a committee within the Privy Council composed usually of elected members of Parliament.

While the Cabinet specifically deals with the regular, day-to-day functions of the King-in-Council, occasions of wider national importance—such as the proclamation of a new Canadian sovereign following a demise of the Crown or conferring on royal marriages—will be attended to by more senior officials in the Privy Council, such as the prime minister, the chief justice of Canada, and other senior statesmen; though all privy councillors are invited to such meetings in theory, in practice, the composition of the gathering is determined by the prime minister of the day.

[11] The Constitution Act, 1867, outlines that persons are to be summoned and appointed for life to the King's Privy Council by the governor general,[10] though convention dictates that this be done on the advice of the sitting prime minister.

Generally, in all things I shall do as a faithful and true servant ought to do for His Majesty.Provincial premiers are not commonly appointed to the Privy Council, but have been made members on special occasions, such as the centennial of Confederation in 1967 and the patriation of the constitution of Canada in 1982.

On Canada Day in 1992, which also marked the 125th anniversary of Canadian Confederation, Governor General Ramon Hnatyshyn appointed 18 prominent Canadians to the Privy Council, including the former Premier of Ontario David Peterson, retired hockey star Maurice Richard, and businessman Conrad Black (who was later expelled from the Privy Council by the Governor General on the advice of Prime Minister Stephen Harper[13]).

[20] When he served as viceroy, John Campbell, Marquess of Lorne, put an end to the practice of the governor general presiding over Privy Council meetings, other than for ceremonial occasions.

[24][25] Two years later, the Privy Council again met before the Queen, this time in Halifax, Nova Scotia, to confirm the appointment of Georges Vanier as governor general.

David Brown, an official in the Privy Council Office, told The Globe and Mail that, had the Privy Council rejected the Prince of Wales' engagement, none of his children would have been considered legitimate heirs to the Canadian throne, thus setting up a potential break in the unified link to the crown of each of the Commonwealth realms, in contradiction to the conventional "treaty" laid out in the preamble to the 1931 Statute of Westminster.

[27] To mark the occasion of her Ruby Jubilee, Queen Elizabeth II, on Canada Day, 1992, presided over the swearing in of new members of her Privy Council.