The human microbiota is the term for the collection of microorganisms that live on or within the human body. They out number our own cells by an order of magnitude, they provide a metabolic capability equivalent to a human organ and essentially shape our ability to stay alive. Recent evidence has highlighted a potential role of microbes in back pain. This talk will provide a comprehensive overview of the human microbiota and discuss the current literature in relation to how it may be related to back pain.