Cooperation among the parliaments of CEI Member States has always been an important part of the CEI operation. The Parliamentary Dimension, along with the Governmental and the Business Dimensions, is positioned as one of the three pillars of the CEI. Throughout the years, the institutional establishment of the Parliamentary Dimension has undergone a transformation process, which has been formalised with the adoption of the Rules of Procedure of the CEI Parliamentary Dimension.

The Parliamentary Dimension includes several bodies: the Parliamentary Assembly; the Parliamentary Committee; the three General Committees (on Political and Home Affairs; on Economic Affairs; on Cultural Affairs).

The annual chairmanship of the Parliamentary Dimension rotates according to the annual CEI Presidency.