Congressional Member Organization

A congressional caucus is a group of members of the United States Congress that meets to pursue common legislative objectives. Formally, caucuses are formed as congressional member organizations (CMOs) through the United States House of Representatives and the United States Senate and governed under the rules of these chambers. In addition to the term caucus, they are sometimes called conferences (especially Republican ones), coalitions, study groups, task forces, or working groups. Many other countries use the term "parliamentary group"; for example, the UK Parliament has many all-party parliamentary groups.

The largest caucuses are the party caucuses and conferences in the United States Congress, which are the partisan caucuses comprising all members of one house from one party (either the Democrats or the Republicans). These are the House Democratic Caucus, House Republican Conference, Senate Democratic Caucus, and Senate Republican Conference.

The caucuses meet regularly in closed sessions to set legislative agendas, select committee members and chairs, and hold elections to choose various floor leaders. They also oversee the four Hill committees, political party committees that work to elect members of their own party to Congress.

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