Parliament is the law-making body but it is not the executive. It does not administer or enforce the laws. It is far too big to do so effectively and if it tried it would have to neglect its law-making and critical functions. Executing, administering, enforcing and carrying out the laws is the job of the cabinet supported by the various Government Departments, Boards, Commissions and so forth. The Cabinet makes and implements Government policy within the framework of the laws parliament has made.
The Prime Minister is appointed by the Governor-General, but the choice is normally a foregone conclusion since it can be assumed that he will be the leader of the party having the largest number of seats in the House of Commons.
The other Members of the Cabinet are chosen by the Prime Minister and appointed by the Governor-General on the Prime Minister's advice. The number of Ministers may vary depending upon the pleasure of the Prime Minister and the number of departments their government will govern with. Normally the number of Ministers is about thirty, most of whom head Government departments. There are a few Ministers without departmental responsibilities who are usually given a special function to perform. One such Minister is normally a Senator and is the Government Leader in the Senate; ordinarily there are no Ministers in the House. The rest including the Prime Minister must be members of the House of Commons or must become so within a short time after their appointment. They must stand together on Government Policy. A Minister who cannot accept that policy must resign.
The Cabinet is legally a Committee of the Privy Council. The Privy Council in its plenary form plays no part in government and for many years has held only very occasional formal meetings with the Queen of the Governor-General present. All Cabinet Ministers must be Privy Councilors, and they remain so even after they have left the Cabinet. Usually, every province is represented in the Cabinet unless that province has failed to return any Members supporting the Government. The most populous provinces, such as Ontario and Quebec, are likely to be represented in the Cabinet by several ministers.
Although answerable to Parliament, the Cabinet is a powerful body because of the great responsibilities delegated to it. It controls the departments of government and administers a wide range of laws and polices. Under the authority of various Acts of Parliament, it is empowered to make regulations which can have a far-reaching effect on the lives of the people. It administers massive economic and social programs. It controls huge expenditures which, although approved and appropriated by Parliament, are of such complexity that total financial control by Parliament is in practice impossible.