Dr. Nagashima has used her specialization in political science to engage in research and policy advocacy on women’s and girls’ leadership, research on the gender gap, and a wide range of other activities, such as promoting public awareness to achieve SDGs and related social agendas. She is also a part-time lecturer at Universities, and a commentator for Asahi Shimbun [Newspaper] Digital. Since 2021, she also serves as an expert member of the Council for the Promotion of Gender Equality Collaboration, Gender Equality Bureau, Cabinet Office.While studying refugee reception policies in developed countries at the Graduate School of Political Science at Waseda University, she also worked as an intern/researcher at the international organizations and CSOs. While working as a research assistant at Waseda University, she was involved in a campaign for Africa, which led her to manage various NGOs and foundations, engage in policy advocacy, and plan and manage campaigns by artists and athletes. She got PhD. in political science in 2010. Her book is Issues Concerning FGM (Female Genital Mutilation) and the Concept of Gender-Based Persecution: A Study from the Perspective of Feminist International Law (Waseda University Press, 2010).