The UNFCCC workshop on carbon dioxide (CO2) capture and storage as clean development mechanism (CDM) project activities was held on 22 May 2006, in Bonn, Germany, in conjunction with the twenty-fourth session of the Subsidiary Body for Scientific and Technological Advice. The participants discussed issues relating to the consideration of CO2 capture and storage as CDM project activities under four main topics: project boundary, leakage, permanence and other issues. This report is to be considered by the Conference of the Parties serving as the meeting of the Parties to the Kyoto Protocol at its second session, together with submissions from Parties and recommendations by the CDM Executive Board on methodological issues