Technical advances of next-generated sequencer for metagenomics and mass spectrometer for metabolome analysis open the door to integrate the role of microbiota on many kinds of physiology and pathology in the body. At the same time, integrated microbiota science leads to fusion of immunology, metabolism, and neuroscience to understand the whole body as networks between various organs by watching the body as "forest". In this International Session, we invite several extraordinary pioneers in Japan and overseas, and they will talk and discuss the big topics in view of different aspects. Additionally, we will choose a few original sciences from among the public.