This report provides a summary of the Subsidiary Body for Scientific and Technological Advice (SBSTA) event on quantified economy-wide emission reduction targets by developed country Parties. The event was held in conjunction with the fortieth session of the SBSTA in Bonn, Germany, on 8 and 11 June 2014. The event was preceded by a technical briefing on land use, land-use change and forestry (LULUCF) reporting held in conjunction with the thirty-ninth session of the SBSTA in Warsaw, Poland, on 12 November 2013, a summary of which is also contained in this report. As part of the process of clarification of the quantified economy-wide emission reduction targets by developed country Parties under the work programme, the event addressed assumptions and conditions related to these targets, the identification of common elements for measuring the progress towards the achievement of the targets and comparability of mitigation efforts with regard to the role of LULUCF and carbon credits from market-based mechanisms.