2018 - 2021 Climate policy under Trump administration and California state
2016 - 2020 Reappraisal of Japan's fisheries law and policy in the global era: From the viewpoint of the compatibility between international law and national law and policy
2015 - 2019 management strategies for decentralized treaty process
2010 - 2015 Multidisciplinary Study on Japanese Practice for implementation of Environmental Treaties: Linkage between International Law and National Law and Policy for Environmental Protection.
2010 - 2012 Policy reorganization and Institutional design
2006 - 2011 A Sustainable International Framework for the Prevention of Global Warming
久保 はるか. Book reviews: K. Yorimoto, Policy making of recycling and citizen participation. Review of environmental economics and policy studies. 2010. 3. 1. 79-84
久保 はるか. Comments. Public finance and public policy. 2007. 29. 1. 33-38