Meet the Leadership Team

ArendAnthony Clark Arend, Director of MSFS and Senior Associate Dean of Graduate and Faculty Affairs of the School of Foreign Service, is a Professor of Government and Foreign Service at Georgetown University. With Professor Christopher C. Joyner, he founded the Institute for International Law & Politics at Georgetown and served as co-director of the Institute from 2003-2008. He is also an adjunct professor of law at the Georgetown University Law Center. Prior to coming to Georgetown, he was a Senior Fellow at the Center for National Security Law at the University of Virginia School of Law. He has also served as an Articles Editor for the Virginia Journal of International Law.

Dr. Arend's teaching and research interests are in the areas of international law, international organization, international relations, international legal philosophy, and constitutional law of United States foreign relations. Dr. Arend is the author, co-author, or co-editor of several books, including: Human Dignity and the Future of Global Institutions (with Mark Lagon); Legal Rules and International Society; International Rules (with Robert J. Beck and Robert Vander Lugt); International Law and the Use of Force: Beyond the United Nations Charter Paradigm (with Robert J. Beck); Pursuing a Just and Durable Peace: John Foster Dulles and International Organization; The Falklands War: Lessons for Strategy, Diplomacy, and International Law (with Alberto R. Coll). He has also written articles in numerous journals.

Dr. Arend received a Ph.D. and an M.A. in Foreign Affairs from the Woodrow Wilson Department of Government and Foreign Affairs of the University of Virginia. He received a B.S.F.S., magna cum laude, from the Edmund A. Walsh School of Foreign Service at Georgetown University.

He edits the blog Anthony Clark Arend and is a member of the Council on Foreign Relations.

View Anthony Clark Arend's ExploreGeorgetown profile.


Rachel Yang Antoun, Assistant Director of External Affairs, works closely with Associate Director in developing relationships with external organizations in the public, private, and nonprofit sectors in the U.S. and abroad. In addition, she provides support to students in all aspects of their internship search by conducting workshops on internship and career searches, holding one-on-one advising sessions, providing written recommendations, and more. She also organizes MSFS DC Days and the NYC Trip.  

Before joining the MSFS program, Rachel worked at the University of Michigan as the Program Coordinator in their Confucius Institute and most recently as the Graduate Coordinator serving PhD students in the Electrical Engineering and Computer Science department. She has also spent a considerable amount of time living and working abroad, namely in Taipei, Taiwan and Beijing, China.  

Rachel earned her M.A. in Higher Education from the University of Michigan and a B.A. in International Affairs from James Madison University.


Cris DinuCristina Dinu, Associate Director of Admissions, engages with prospective students through information sessions and individual appointments and assists them in their search for the perfect program. In addition to her work on campus, Cris meets prospective students through recruitment trips both domestically and internationally.

Cris came to Georgetown University in 2003 to work for former National Security Advisor Anthony Lake and former Ambassador to the United Nations Donald McHenry. Prior to joining MSFS in 2012, she worked in the Office of International Programs and the BMW Center for German and European Studies. A native of Romania, Cris holds a Bachelor of Arts degree from St. Lawrence University and a Master of Arts in French Language and Literature from the University of Maryland, College Park.


Erin E. Guild, Associate Director, oversees academic and alumni affairs for the Master of Science in Foreign Service program. In addition to supporting students, faculty, and alumni, Mr. Guild supports the efforts of the MSFS Advisory Board as it serves to strengthen the program's academic and professional opportunities. Mr. Guild works closely with the Director of Academic Affairs, the Assistant Director of External Affairs, and the Communications and Events Coordinator. He also serves on the MSFS Admissions Committee.

Prior to joining the MSFS program, Mr. Guild served as Director of Admissions and Registrar to the School of Advanced International Studies of The Johns Hopkins University. He has worked in institutions of higher education since 1997. Prior to that, Mr. Guild worked as an aide on the United States Senate Committee on Labor and Human Resources.

Mr. Guild earned his Bachelor of Arts degree from the State University of New York at Binghamton. He earned a Master of Science in Student Affairs in Higher Education degree from Colorado State University and a Master of Public Relations & Corporate Communications from Georgetown University. Mr. Guild is currently pursuing his doctorate in Education with an emphasis in College and University Leadership.


Tennille HaegeleTennille H. Brown, Director of Admissions, is responsible for supervising the admissions and scholarship process for MSFS. Prior to joining the MSFS program, she was at George Mason University’s School of Public Policy for six years, first as Assistant Director then Director, overseeing admissions for the Ph.D. program and six Master’s degree programs. Before relocating to the DC area, she worked in the Enrollment Services office at Tallahassee Community College (TCC). While obtaining her Master’s degree, she worked in the Office of Student Life and Development at San Diego State University, assisting in the development and organization of their orientation programs. She has worked in the higher education field for 16 years.

Ms. Brown earned her Bachelor of Arts degree in Psychology from Minnesota State University, Moorhead. She earned a Master of Arts in Postsecondary Educational Leadership from San Diego State University.



Mei-Ling Klein, Assistant Director of Finance and Administration, is responsible for the oversight and management of all program funds, human resources administration, and facilities and technology management.

For nearly three years, Mei-Ling served as the Program Administrator for the Global Human Development Program at Georgetown. Prior to coming to the School of Foreign Service, she held several administrative positions in the McDonough School of Business. Before Georgetown, Mei-Ling spent a decade in Switzerland in a variety of academic administrative positions, including Associate Director of External Relations and Director of Admissions at the Leysin American School and Director of Annual Giving at the American School of Switzerland. She also served for seven years as the Director of Admissions and Financial Aid at the American School in Japan. Mei-Ling holds an M.S. in Business Education from the University of Southern Illinois and a B.A. in English Literature from Tamkang University in Taiwan.


Sarah Krauss, Director of Academic Affairs, works with faculty and students on course offerings, registration, degree requirements, and progress toward graduation for the program. She serves as academic advisor for students pursuing joint degrees with MSFS and works closely with the MSFS Student Representatives to enhance the student experience. Sarah also manages the MSFS Oral Exams and New Student Orientation. 

Before MSFS, Sarah spent four years working in the Office of Undergraduate Studies at The George Washington University, most recently as Associate Director. Prior to her time at GW, Sarah worked at the Center for Academic Advising and First Year Programs at Lasell College and previously served in the Office of Career Services at the Fletcher School of Law and Diplomacy at Tufts University. Sarah holds an M.Ed. in Higher Education from Harvard University and a B.A. in English Literature and Philosophy from the University of Vermont.


Kristen Voorhees, Events and Communications Coordinator, oversees and implements strategic communications for the MSFS program. Additionally, she coordinates and manages events held by MSFS, including orientation and graduation. Kristen is the advisor to the programs' student groups. Before joining MSFS, Kristen worked as Outreach Coordinator for Counterpart International, a global development non-governmental organization operating in more than 25 countries on issues including civil society and governance, nutrition, access to education, and climate resiliency.

Kristen earned her Bachelor of Arts degree in Political Science with a focus on International Relations from Binghamton University in New York. She completed her Masters of Public Administration with a focus on International Development from The George Washington University. 


Concentration Chairs

Nicole Bibbins SedacaProfessor Nicole Bibbins Sedaca - Chair, Global Politics and Security

Professor Bibbins Sedaca is Professor in the Practice of International Affairs and Concentration Chair for Global Politics and Security. At MSFS, Professor Bibbins Sedaca teaches courses in policy innovation, ethics and decision making, and religion and international affairs. 

Prior to joining the MSFS leadership team, Prof. Bibbins Sedaca served in a variety of roles in the US Government, non-governmental organizations, and academia.  Most recently she directed the Washington DC office of a diplomatic advisory group, called Independent Diplomat.  She served as an adjunct professor in Georgetown University’s Master of Science in Foreign Service (MSFS) program from 2010 until joining MSFS full-time. She also served in the U.S. Department of State from 1997 – 2007 on a range of issues including democracy promotion, human rights, refugee issues, counterterrorism, and human trafficking. Most recently she served as Senior Director for Strategic Planning and External Affairs for Democracy, Human Rights and Labor, as well as Senior Advisor to the Under Secretary of State for Democracy and Global Affairs. Following her government service, she launched and directed the International Republican Institute’s local governance program in Ecuador, and also taught at the Universidad San Francisco de Quito in Ecuador.  

She earned her Master of Science in Foreign Service from Georgetown University and Bachelor of Art in International Relations from The College of William and Mary. She also studied at Humboldt Universitaet in Berlin, Germany, while on a Rotary International Scholarship. She chairs the board of the International Justice Mission, and has also served on the Boards of the Institute for Global Engagement, Georgetown University’s School of Foreign Service, the William and Mary Washington Office, and the Fund for William and Mary.


Professor Erwin Tiongson - Chair, International Development and Deputy Director of the MSFS Program

Prior to joining Georgetown in 2014, Erwin was a Senior Economist at the World Bank and served in the Europe and Central Asia Region and, more recently, in the Latin America and Caribbean Region. He first joined the World Bank in 2003 through its Young Professionals Program. He also served as staff member of the International Monetary Fund from 1997-2003 and served as Associate Professor at the Asian Institute of Management from 2009-2011, where he remains a Nonresident Research Fellow. He is a Research Fellow of Das Institut zur Zukunft der Arbeit (IZA) (Institute for the Study of Labor), External Research Fellow of the Centre for Research and Analysis of Migration (CReAM) at the University College London, and Senior Fellow of the Institute for the Study of International Migration (ISIM).

Erwin holds a Ph.D. and an M.Phil. in Economics from The George Washington University, an M.P.P. from Georgetown University, an M.A. in Economics from Fordham University, and a B.A. in Philosophy from the Ateneo de Manila University. He was born and raised in Nueva Vizcaya, Philippines.


Professor David Wallis - Chair, Global Business and Finance

Professor Wallis is Professor in the Practice of International Affairs and Concentration Chair for Global Business and Finance, MSFS.

Prior to joining the MSFS leadership team, Professor Wallis engaged in a global business career working within the financial services industry. This experience was geographically based in London, New York and Tokyo and has included senior executive positions in insurance, investment banking and asset management. Specifically within the insurance industry, Professor Wallis was the Chief Risk Officer and subsequently President and Chief Executive Officer of Ambac Inc., a New York Stock Exchange Company where he also sat on the Board of Directors. Subsequently Professor Wallis worked at AIG both in New York and Tokyo, and was latterly responsible for AIG’s Regional Financial Planning & Analysis Groups based in Tokyo.

Professor Wallis holds an Honors Degree in Economics from Downing College, Cambridge, an MBA from the City University Business School, London and attended the Program for Manager Development at the Fuqua School of Business, Duke University. He also qualified MCT under the Association of Corporate Treasurers in the UK. Professor Wallis served as an Adjunct within Georgetown’s MSFS program in 2012 and 2013.