This Part deals with how members and Senators are chosen for the Parliament, and related rules.

Division 1 deals with Senators for Queensland. These Senators are chosen by the people of Queensland voting as one electorate.

Division 2 deals with Senators for the Territories, setting out some rules relating to Senators of Territories (such as numbers of Senators, powers, privileges and immunities, and term of service).

Division 3 deals with representation of States and Territories in the House of Representatives. The number of members of the House of Representatives is based on the population of the Commonwealth, the States and the Territories, as determined by the Australian Statistician.

The number of members is worked out using a quota, which is the number of people of the Commonwealth (excluding the populations of Territories) divided by twice the number of Senators for the States. This produces a national average population for each member.

For States, the number of members is worked out by dividing the population which is worked out for the State by the quota (rounding up if the remainder is more than 0.5).

For Territories, the number of members is worked out the same way, except that the result is rounded using the harmonic mean. The harmonic mean is a method of rounding that improves proportionality and addresses under-representation of Territories by minimising the gap between the average population per member in the Territories, compared with the national average population for the States (as measured by the quota).