Early events in microbial colonization have a profound effect on physiology and immune education in the gut, thereby impacting disease susceptibility and infant health outcomes, yet we know remarkably little about the natural history of how the microbiome forms in children. However, recent research is connecting the importance of mother to child microbial transmission on establishment of the infant microbiome, as well as the essential role of the microbiome in health outcomes for the developing child. Therefore, this conference will focus on the importance of the microbiome to maternal-child health. This conference will cover topics such as microbiome and pregnancy outcomes, the development of the infant gut microbiota, the impact of the mother and infant microbiome on neurodevelopment and the relationship between nutrition, breast milk composition and infant gut microbiome. Overall, this conference attempts to explore the role of the microbiome from pre-pregnancy, throughout pregnancy, and in the infants, and evaluate the impact of nutrition, stress and other factors on these microbiomes and ultimately on infant development, including neurodevelopment and metabolic health. By assembling such a diverse group of scientists who usually attend different meetings (either focused on women's health or on infant health), this conference will provide a forum for developing engaged discussions and collaborations that will help move the field forward. Further, attendees will be exposed to a breadth of science unassembled to date. In addition, as this field is still in its infancy, many questions remain, such as the existence of an in-utero microbiome and this conference will include a healthy debate between two scientists with opposite view on the issue.