Yumi Hiwatari was a Visiting Fellow at CIS in 2005–06. She is a Professor of International Relations at Sophia University in Tokyo and has written widely on U.S.-Japan relations and Japanese defense politics. Her current research interests concern the comprehensive review of Japan’s defense policy, especially the policy changes that took place during the Koizumi administration and their impact on Japan Self-Defense Forces. She has an essay on that topic in Breakthroughs, Spring 2006.
In 2012, Hiwatari finally finished her book on Japan's national security. The book title is Defending Strategy: Rethinking Japan's National Security (Senshu Bouei Kokufuku no Senryaku). The publisher is Minerva Shobo Japan. The book consists of five chapters, including strategy, U.S.-Japan alliance, defense budget, structural reform, and civil-military relations. It is available only in Japanese.
Hiwatari is Chairperson of Department of Global Studies and Director of Sophia Institute of International Relations. Faculty of Global Studies was established in April 2014 and Sophia Institute of International Relations in July 2015.