Plenary sittings are meetings of all House Members, and it is here that the final will of the House is determined. Plenary sittings are open to the public in principle, and one-third or more of all Members must be present for a plenary sitting to be held. Business is decided by the agreement of a majority of Members present, except for special cases.
When the Diet is in session, the House of Representatives usually holds its plenary sittings at one ofclock in the afternoon on Tuesdays, Thursdays, and Fridays, and the House of Councillors at ten ofclock in the morning on Mondays, Wednesdays, and Fridays.