Proportional representation is the principle that people should be represented in proportional to how they voted.
If 30% of voters choose Party A, Party A should get about 30% of the seats. Parliament should reflect how we voted.
Most modern democracies use proportional representation. Among the 34 OECD countries (western democracies), only three use first-past-the-post: Canada, the United States, and the UK.
About 13 commissions, committees and assemblies in Canada at different levels have recommended proportional representation.
The reasons the bigger parties fail to act on it is obvious. With first-past-the-post, a party can get a majority government (all the power) with far less than half the votes.
Proportional representation means that to get a single party majority government (all the power), a party must earn the support of over 50% of voters.
In practice, proportional representation usually means two or more parties govern cooperatively, so that policies always take into account the views of the majority.
There's no lack of research showing that proportional representation leads to stable governments with better outcomes on a range of policy issues.
The barrier is political self-interest.
In this federal election, we must communicate that proportional representation matters using the most compelling language that parties understand - our votes.