The committees are composed in principle of at least one commissioner or deputy commissioner per Member State and the experts designated by them. They meet in principle twice a year, but sometimes more. Committee work in some cases are prepared by working groups. The working groups are composed according to the missions entrusted to them and may also include qualified external persons.
Observer states are invited to actively participate in committees and working groups. Accredited non-governmental organizations may be heard by committees or participate in working groups.
The work of committees and working groups are prepared by the Secretariat and the delegations. The Secretariat shall prepare the draft agendas and provides the minutes and the implementation of the measures decided by the committees.
Thanks to the close integration of the contributions of national delegations, representatives of the profession, experts and the secretariat, most projects developed by committees and working groups enjoy a climate of consensus. This consensus enables effective decision making despite the rule of unanimity prevails in the plenary meeting.