This report identifies lessons arising from the IGAD-led mediation process from December 2013 to August 2015 to address the conflict in South Sudan. It is the outcome of a lessons learned exercise initiated, led and owned by IGAD. It complements a report of April 2016, in which the IGAD Special Envoys, upon conclusion of their mandate, provided a detailed account of the IGAD-led mediation process, including an assessment of its different phases and the evolution of the parties’ positions.