His research interests focus on language ideology, language endangerment, history of linguistics, and social aspects of foreign language learning. Recent publications include Higashi ajia ni okeru gengo fukko [Language Revitalization in East Asia] (co-edited with Shin Matsuo, Sangensha 2010), Language Life in Japan (co-edited with Christian Galan, Routledge, 2011), and Mezase! Ryukyu shogo no iji [In Pursuit of Ryukyuan Language Maintenance] (co-edited with Michinori Shimoji, CoCo Shuppan 2011). He is currently co-editing the Handbook of Ryukyuan Languages.