According to the Rules of Procedures for the preparatory process, entities having received a standing invitation from the UN General Assembly to participate in the capacity of observers in the session and work of all international conferences convened under its auspices, UN specialized agencies, representatives of UN agencies and associate members of regional commissions may participate as observers, without the right to vote, in the deliberations of the Preparatory Committee. No accreditation or invitation is required.

Other international organizations may participate by invitation. No accreditation is required. In order to receive an invitation, international organizations other than the ones mentioned above may write to the Executive Director, WSIS Executive Secretariat, c/o ITU, Place des Nations, CH-1211 Geneva 20, Switzerland or send a fax to +41 22 730 63 93 and announce their interest to participate in the PrepCom and the Summit. Once invited, the invitation is valid for the whole preparatory process and the Summit events (Geneva and Tunis).

Nevertheless, registration is required for each meeting.