The Plenary Sessions represent the culmination of the legislative work done in committees and in the political groups.

These sessions are where the Parliament formally sits to vote on EU legislation and adopt its position on political issues. The MEPs (the Members of the European Parliament) meet around once a month in Strasbourg for a four-day part session from Monday to Thursday. In addition to these twelve annual Strasbourg sessions, the Parliament may also meet in additional two-day plenary sessions in Brussels up to six times a year.

The European parliament has 754 elected members from 27 Member States of the European Union and conducts its plenary debates in 23 languages. Since April 2012, the European parliament welcomes 12 Croatian observers.

The agenda for the plenary sitting is published online. This agenda is deemed to be definitive only after the adoption by the Conference of Presidents (of political groups) - in principle each Thursday before the Strasbourg part-session.