Former US Ambassador to Russia Rejoins Mayer Brown as Partner

John Sullivan, former deputy secretary of state and U.S. ambassador to Russia, has rejoined Mayer Brown as a partner in the Washington, D.C., and New York offices, the firm announced. Sullivan's practice will center on issues relating to clients' business operations, "including global risk, US sanctions and export controls, international trade disputes and regulation, and foreign investment." Sullivan served as ambassador to Russia from 2020 to 2022 and as acting secretary of state from March to April 2018. He is also a distinguished fellow at Georgetown University's School of Foreign Service and a distinguished senior fellow at Columbia University School of Law's National Security Law Program.