The role of the president is to lead the Commission, and give direction to the Commission and the Union as a whole. The treaties state that "the Commission shall work under the political guidance of its president" (Article 219 TEC), this is conducted through their calling and chairing of meetings of the college of Commissioners, their personal cabinet and the meetings of the heads of each commissioner's cabinet (the Hebdo). The president may also force a Commissioner to resign. The work of the Commission as a body is based on the principle of Cabinet collective responsibility, however in their powers they act as more than a first among equals. The role of the president is similar to that of a national Prime Minister chairing a cabinet.