Kazuyoshi Tsutsui is Professor at the Department of Biology, Waseda University. He has contributed to the advancement of neuroendocrinology by his studies focusing on the discovery of novel neurosteroids and neuropeptides, and the demonstration of their mode of actions and functional significances. He has published over 330 papers including Nature Medicine, Nature Communications, Proc. Natl. Acad. Sci. USA, Frontiers in Neuroendocrinology, Progress in Neurobiology, Mass Spectrometry Reviews, Endocrinology, J. Neuroscience, etc. He was awarded Zoological Society Prize of Japan, Farner Medal from the International Society for Avian Endocrinology, and Bargmann-Scharrer Lectureship Award from the International Federation of Comparative Endocrinology Societies.