Members of parliament are usually associated with a political party, although some members do sit independently. The Senate is the Upper House of Parliament. Members of the Senate are appointed by the Governor General upon recommendation by the Prime Minister. In addition to its consideration of parliamentary legislation, the Senate is also asked to investigate important economic and social issues. With specific exceptions, all parliamentary legislation must be approved by the House of Commons, the Senate and the Governor General before it can become law.
Most parliamentary legislation is introduced by the government.
By convention, the political party with the most elected members in the House of Commons will take the leading role in forming the government. If it has fewer than 151 seats, the leading party will seek the cooperation of other parties. The leader of this party becomes the Prime Minister. The party with the second highest number of seats usually becomes the Official Opposition. Its leader becomes the Leader of the Opposition.