Microbiomes are communities of microorganisms living in soil and other habitats. In recent years, a new wave of research into understanding soil microbiomes has emerged, with stakeholders across the supply chain recognising the fundamental importance of these communities in optimising both crop and soil health. Despite these advancements, many soil microorganisms and their ecological functions remain only partially understood. Understanding and utilising soil microbiomes for a more sustainable agriculture summarises the wealth of recent research in this important area. It reviews advances in techniques for analysing soil microorganisms, the composition and dynamics of soil microbial communities, the ecosystem services they support and how they can be enhanced.