This conference will last 2.5 days, from April 19th 1:30 p.m. to April 21st 4 p.m. It will take place right in the center of Paris, in the heart of “Quartier Latin” in the prestigious Grand Amphithéâtre of the Museum National d'Histoire Naturelle (https://www.mnhn.fr/fr). Note that for space constraints, we won’t be able to take more than 300 registrations so that registrations will be accepted on first-come first-served basis. Registration will open by November 25, 2016 and be closed by January 31, 2017 (please, register online at https://symposium.inra.fr/holobiont-paris2017). The objective of the International Conference on Holobionts, Paris 2017 is to, for the first time, bring scientists together who are interested holobiont systems and their study. This conference will highlight major advances in defining the key roles of host-borne microbiota in the ecology and evolution of higher organisms and the potential implications for human health, food production and ecosystem functioning. In addition, the conference will offer a platform for debate related to the definition, assembly and evolution of holobionts. By bringing a range of holobiont researchers together, the International Conference on Holobionts seeks to help consolidate the field, facilitate exchange across systems and approaches and stimulate future development in this emerging field. Scientific program This conference will address the following topics: 1. Holobionts and evolution 2. Emerging approaches to holobiont research 3. Microbiota and host health 4. Mechanisms for holobiont assembly 5. Metabolic interactions between host and microbiota