A workshop on the preparation of fourth national communications by Parties included in Annex I to the Convention (Annex I Parties) was organized by the UNFCCC secretariat and held in Dublin, Ireland, from 30 September to 1 October 2004. The workshop was designed to facilitate the timely submission of fourth national communications by Annex I Parties, which are due by 1 January 2006, and encourage the exchange of views among technical experts on the comparability and transparency of the information in the communications. This document describes the workshop and highlights some good practices and examples of collecting, assessing and reporting of information in national communications