Rachel Wellhausen's primary field of interest is the political economy of international investment and finance. Her book "The Shield of Nationality: When Governments Break Contracts with Foreign Firms" (2015) examines the conditions under which governments maintain or break the contracts they enter into with foreign investors. Fieldwork included interviews with executives and government officials in Ukraine, Moldova, and Romania, with follow-up work in Russia and Azerbaijan. The dissertation on which the book is based won the Mancur Olson award from the American Political Science Association for the best dissertation in political economy in 2011-2012. Professor Wellhausen is co-editor of Production in the Innovation Economy (2014), which resulted from MIT's interdisciplinary project on innovation and production. She has published in the American Political Science Review, International Studies Quarterly, Journal of Conflict Resolution, Business and Politics, and other outlets.