The Subsidiary Body for Scientific and Technological Advice (SBSTA), at its thirtyseventh session, agreed on the work programme on the revision of the guidelines for the review of biennial reports and national communications, including national inventory reviews, for developed country Parties. The Conference of the Parties (COP) adopted, by decision 23/CP.19, the “Guidelines for the technical review of information reported under the Convention related to greenhouse gas inventories, biennial reports and national communications by Parties included in Annex I to the Convention”. The annex to that decision contains a placeholder for the “UNFCCC guidelines for the technical review of greenhouse gas inventories from Parties included in Annex I to the Convention”. These guidelines will be an update of the “Guidelines for the technical review of greenhouse gas inventories from Parties included in Annex I to the Convention”, as contained in the annex to decision 19/CP.8 (hereinafter referred to as the UNFCCC Annex I inventory review guidelines). Substantive discussion on the revised UNFCCC Annex I inventory review guidelines began at SBSTA 40 and will continue at SBSTA 41 with a view to a decision being adopted at COP 20.