Duncan B. Hollis is Laura H. Carnell Professor of Law at Temple University's Beasley School of Law, a non-resident fellow at the Carnegie Endowment for International Peace, and an elected member of the OAS Inter-American Juridical Committee and the American Law Institute. He is the editor (with Allen Weiner) of one of the leading U.S. textbooks, International Law (7th ed. 2018) and he co-edited and co-authored National Treaty Law & Practice (2005), which surveyed nineteen States' law and practice involving treaties. Prior to joining the Temple faculty, Professor Hollis served from 1998 to 2004 in the Office of the Legal Adviser at the U.S. Department of State. During his tenure at the State Department, he worked for several years as the attorney-adviser for treaty affairs, addressing legal and constitutional issues associated with U.S. treaties.