"Unilateral CDM" projects refer to those CDM project activities that do not have an Annex I Party letter of approval at the time of registration of the project.
In general, written approval must be provided from each Party involved:
The designated operational entity shall:
- Prior to the submission of the validation report to the Executive Board, have received from the project participants written approval of voluntary participation from the designated national authority of each Party involved, including confirmation by the host Party that the project activity assists it in achieving sustainable development (3/CMP.1, Annex, paragraph 40(a)).
However, the Executive Board has clarified that approval from an Annex I Party is not required at the stage of project registration.
The Board agreed that the registration of a CDM project activity can take place without an Annex I Party being involved at the stage of registration. Before an Annex I Party acquires certified emission reductions from such a project activity from an account within the CDM Registry, it shall submit a letter of approval to the Board in order for the CDM Registry administrator to be able to forward CERs from the CDM Registry to the national registry of the Annex I Party (EB 18, paragraph 57).
Project activities that do not have an Annex I Party letter of approval at the time of registration are known as "unilateral CDM" projects.