Kiyoshi TAKAHASHI is a head of the Trans-Boundary Impacts & Mitigation Modeling Section, Center for Social and Environmental Systems Research, National Institute for Environmental Studies (NIES), Japan. He has been engaged in research projects for developing an integrated assessment model for climate policy analyses (AIM: Asia-Pacific Integrated Model) since 1996 and has contributed to the projects through the improvement of model modules for analyzing climate change impacts on agriculture, water resources, and natural ecosystems at global scale. Based on his expertise in the research field, he also contributed to the development of the fourth and the fifth assessment reports of the IPCC as a lead author.