The fifth congress of the International Human Microbiome Consortium (IHMC) was held in Luxembourg from the 30th of March to the 2nd of April 2015 under the title: “Future Directions for Human Microbiome Research in Health and Disease”.The congress program was organized into three plenary sessions and six concurrent sessions over three days with plenty of opportunity for discussion and networking. 50 internationally renowned scientists and experts in a diverse range of fields applicable to microbiome research were invited to present their current research. The international reputation of the invited speakers and the comprehensive program attracted a total of 460 paying delegates from many regions of the world, primarily North-America, Europe and Asia.The first plenary session addressed the evolutionary basis of the host-microbiome symbiosis and the significance of the microbiome in human biology and human evolution, while the second plenary session described state-of-the-art research in the role of the microbiome in a wide spectrum of human diseases and disorders. The third plenary session focused on future applications and directions for the field and discussed the challenges of conducting microbiome research in resource-limited regions of the world.The six concurrent sessions were designed to provide more in-depth exposure to the current approaches and methods for microbiome research. These sessions focussed on: computational and integrative “-omics” analyses, the causative role of microbiome in diseases, emerging model systems, new methodologies and tools, interventions for microbiome disorders, and microbiome biobanking.The last session of the Congress was a “Futures” Roundtable. The open floor discussion brought all of the Congress participants back together for an opportunity to discuss where this field is going and what is needed to advance it.Throughout the three days of the main congress, there were multiple sessions dedicated to the presentation of the accepted posters. Of a total of 289 confirmed abstracts 193 posters were displayed at the congress. Finally, at the formal closing of the congress, an award, sponsored by the BMC Microbiome journal, was handed to the best poster.