The unicameral Parliament of Finland gathers for its first plenary session.

Unicameralism is a type of legislature consisting of one house or assembly that legislates and votes as one. Unicameralism has become an increasingly common type of legislature, making up nearly 60% of all national legislatures and an even greater share of subnational legislatures.

The Parliament of Finland is the unicameral and supreme legislature of Finland, founded on 9 May 1906. In accordance with the Constitution of Finland, sovereignty belongs to the people, and that power is vested in the Parliament. The Parliament consists of 200 members, 199 of whom are elected every four years from 13 multi-member districts electing 6 to 37 members using the proportional D'Hondt method. In addition, there is one member from Åland.