Another important factor in determining the political shape of the Sejm are the Deputies' clubs which group members of the Chamber representing similar political views, usually members of the same party or political groups which for some reason decided to act jointly. According to the rules of procedure of the Sejm, a club can be founded by at least 15 Deputies; those political groups whose representatives in the Sejm are not as numerous may form a so-called Deputies' group that should have at least 3 members. Chairpersons of clubs or their deputies as well as the representatives of alliances referred to in art. 9 par. 5 of the Standing Orders are the members of the Council of Seniors. Thus they can influence the proceedings of the Sejm by expressing their views on this forum. Moreover, the clubs and groups submit suggestions about draft schedules on the committees' activity to the Presidium of the Sejm.

Rules of procedure enable the establishment of Deputies' groupings based on a different principle than the shared political views of their members (e.g. the Parliamentary Women's Group, Parliamentary Grouping for the Consumers, Parliamentary Grouping for the Restructuring of the Power Industry).