This technical paper compiles information on the mitigation benefits of actions, initiatives and options to enhance mitigation ambition identified in the submissions by Parties and accredited observer organizations submitted to the secretariat under the Ad Hoc Working Group on the Durban Platform for Enhanced Action (ADP) workstream 2, on pre-2020 ambition. In their submissions, Parties highlighted their efforts in implementing emission reduction pledges by 2020, national actions and their mitigation and adaptation benefits, incentives, and barriers to actions and ways to overcome them. For developing countries, the provision of financial, technological and capacity-building support is deemed essential for the implementation of their pledges. Cooperative initiatives that bring together different stakeholder groups across a number of thematic areas can contribute to enhancing Parties' efforts towards the implementation of the pledges. In their submissions, Parties referred to a number of thematic areas with a high mitigation potential in which further action by 2020 could help to narrow the emissions gap. They acknowledged the role that the ADP can play in assisting Parties in enhancing ambition through technical work and work at the political level by 2015, with a focus on 2013