This volume contains a selection of papers presented at the Rothamsted Millennium Conference "Interactions in the Root Environment - an Integrated Approach". The meeting brought together scientists from a range of disciplines interested in the relationship between soil biology and plant growth, reflected by the contents of the volume. Topics range from root development and nutrient flow, plant-microbe and plant-plant signaling, methods for studying bacterial and fungal diversity, to the exploitation of rhizosphere interactions for biological control of diseases and soil remediation. Authors include many internationally-recognized experts in their field and the contributions range from reviews to research papers. The volume presents a wide-ranging overview of the interactions between plants, microbes and soil. It should prove a useful resource for students and others seeking an introduction to the topic, in addition to scientists already conversant with the area of research.