Zach Vertin served as director of policy in the Office of the U.S. Special Envoy to Sudan and South Sudan from 2013-2016. He was involved in the South Sudan peace process from its inception, providing political, technical and strategic input to the IGAD mediators and engaging the parties to the negotiations on behalf of the United States. The United States was an important peace process supporter throughout the negotiations, offering diplomatic and financial support at the request of the mediation and the IGAD Heads of State.

Vertin was previously a senior analyst at the International Crisis Group, first on multilateral affairs in New York and later in Sudan and South Sudan. His 2019 book, "A Rope from the Sky: The Making and Unmaking of the World's Newest State," chronicles the birth of South Sudan, its civil war and the peacemaking effort. Vertin was later a Fellow at the Brookings Institution and the Woodrow Wilson International Center for Scholars, and taught a regular graduate course at Princeton University on international mediation, negotiation and peace processes. He currently serves in the Biden administration as senior advisor to the U.S. Ambassador to the United Nations.