Professor Spain has served as legal counsel for state parties in international arbitral proceedings. In 2015, she represented two African nations as Respondents in a case before the Permanent Court of Arbitration in The Hague. From 2005-2007, she served as an Attorney-Adviser at the U.S. Department of State, Office of the Legal Adviser where she represented the U.S. before the Iran-U.S. Claims Tribunal in The Hague in the B/61 hearings and in the A/30 case. She earned the U.S. State Department’s Meritorious Honor Award in 2006 and 2007 for her contributions.
As a scholar, Professor Spain has written about the origin, development and importance of international arbitration in providing nations and, increasingly, non-state actors a peaceful alternative for the resolution of disputes.