The multi-partner initial training network entitled “Health-Promoting Cross-talk between Intestinal Microbiota and Humans (CROSS-TALK)” aims at: • Preparing qualified young professionals/researchers and future scientific leaders in the field of an emerging supra-discipline, the human microbiome metagenomics (which calls for new researcher curricula and fosters a dynamic scientific community) through a personal and adapted training program, • Answering key questions on the role of the host-gut microbiota cross-talk in the development and maintenance of a healthy gut. • Developing new concepts and trans-discipline training based on, the integrated scientific programme, laboratory exchanges and dedicated education proposed in CROSS-TALK In order to reach these objectives, CROSS-TALK establishes a collaborative research and training network of 10 network participants and 3 associated partners. This network gathers expertises in complementary disciplines (i.e. microbiology, immunology, cell biology [in-vitro] and molecular biology, in-vivo biology [animal models, humans], biochemistry, proteomics, transcriptomics) and participants from both the academic and private sectors with an excellent track record of collaborative research. The network also offers a complete range of theoretical, practical and complementary training as well as scientific workshops. The excellent scientific network of CROSS-TALK will work together with the young researchers to develop and implement effective training plans tailored to each individual’s requirements. Regular meetings, active networking, connections with other scientific projects in the field and with commercial participants will ensure the success of this project and give the recruited researchers an excellent opportunity to reach their career objectives.