President of the Senate (Australia)
The position is provided for by Section 17 of the Constitution of Australia. The Senate elects one of its members as president at the start of each new term, or whenever the position is vacant. This is usually—though not necessarily—a member of the party or coalition that holds the most seats in the Senate. The largest party in the Senate is not always the governing party, as government is determined by the House of Representatives. The President of the Senate and the Speaker of the House of Representatives may consequently be from different parties.
Crossbencher
The Australian Senate, which uses the Single Transferable Vote form of proportional representation to elect its 76-seat chamber, frequently has a number of Senators on the crossbench that the governing party has to negotiate with to get legislation passed. The 2 July 2016 double dissolution election, for example resulted in a chamber with the Liberal/National Coalition having 30 seats, the Australian Labor Party with 26 seats, the Greens with 9 seats, One Nation with 4 seats and the Nick Xenophon Team with 3 seats. The other 4 seats were each won by Derryn Hinch, the Liberal Democratic Party, Family First, and Jacqui Lambie. The number of crossbenchers increased by two to a record 20. The Liberal/National Coalition government required at least nine additional votes to reach a Senate majority.