The PAP Rules of Procedure provide for each of the five geographical regions to form a regional caucus composed of its members. The Rules also provide for other types of caucuses to be established to deal with issues of common interest as the PAP deems necessary. The Parliament, therefore, has established the Women's Caucus and the Caucus on Youth. Each caucus has a bureau comprising a chairperson, deputy chairperson and rapporteur.
The regional caucuses are established by Rule 83 of the Rules of Procedure. They consist of all the Members from that region. Their main function is to select names from among their members for:
- Nomination for the election of the PAP President or Vice-Presidents.
- Membership to Permanent Committees.
- Participation in other parliamentary bodies or proceedings.
- Perform any other function as assigned to it by the Bureau or the Permanent Committee on Rules, Privileges and Discipline or by resolution of Parliament. Furthermore, the Chairperson of a regional Caucus provides the Bureau or other appropriate authority with the lists of names and other information as decided by the Caucus.