"diet of the realm"; also Swedish: riksdagen [ˈrɪ̌ksdan] ⓘ or Sveriges riksdag [ˈsvæ̌rjɛs ˈrɪ̌ksdɑː(ɡ)] ⓘ) is the parliament and the supreme decision-making body of the Kingdom of Sweden.

Since 1971, the Riksdag has been a unicameral parliament with 349 members (riksdagsledamöter), elected proportionally and serving, since 1994, fixed four-year terms.

The Swedish word riksdag, in definite form riksdagen, is a general term for "parliament" or "assembly", but it is typically only used for Sweden's legislature and certain related institutions.

[8] Riksdag derives from the genitive of rike, referring to royal power, and dag, meaning diet or conference; the German word Reichstag and the Danish Rigsdag are cognate.

[9] The roots of the modern Riksdag can be found in a 1435 meeting in the city of Arboga; however, only three of the estates were probably present: the nobility, the clergy and the burghers.

[10][11] This informal organization was modified in 1527 by the first modern Swedish king, Gustav I Vasa, to include representatives from all the four social estates: the nobility, the clergy, the burghers (property-owning commoners in the towns such as merchants etc.

This reform was a result of great discontent with the old Estates, which, following the changes brought by the beginnings of the Industrial Revolution, was no longer able to provide representation for large segments of the population.

Under the new Instrument of Government[12] (one of the four fundamental laws of the Constitution) enacted in 1974, that task was removed from the Monarch of Sweden and given to the Speaker of the Riksdag.

To make changes to the Constitution under the new Instrument of Government, amendments must be approved twice, in two successive electoral periods with a regular general election held in between.

[15] According to a survey investigation by the sociologist Jenny Hansson, Members of the Riksdag have an average work week of 66 hours, including side responsibilities.

The Riksdag can cast a vote of no confidence against any single cabinet minister (Swedish: statsråd), thus forcing a resignation.

A losing government has one week to call for a general election or else the procedure of nominating a new Prime Minister starts anew.

All Swedish citizens who turn 18 years old no later than on the day of the election and have at one point been registered residents are eligible to vote.

There is a constraint in the system that means that only a party that has received at least four per cent of the votes in the whole country participates in the distribution of seats.