Until someone invents transparent soil, roots will remain imperfectly understood. Their roles in resource capture, disease resistance, symbiosis and stress tolerance are uncovered only after the expenditure of great effort and technical ingenuity. This book describes some remarkable methods, mostly of recent development, by which roots can be rendered more accessible, and measurable, than normally allowed by nature. Split into two sections covering lab and field applications, Measuring Roots: An Updated Approach describes a range of imaging and sensor techniques. These include the use of electrical impedance spectroscopy, multi-electrode arrays, vibrating probes, optodes, confocal microscopy, robotics, geophysical imaging, ground-penetrating radar, sap flow measurement and methods to estimate fine root dynamics. Most chapters provide descriptions of relevant hardware and software and how these are used to investigate particular problems. Examples of the kind of information that each technique can generate are presented in abundant images, many in colour. Anyone studying roots will find something interesting in this multi-author volume, but few will find all of its 18 chapters equally useful. For me, highlights were the chapters on optodes (sensors that non-invasively detect and image the dynamics of specific metabolites such as carbon dioxide and ammonium) and on high-throughput phenotyping of Arabidopsis roots using bespoke robots and imaging software. Quality in terms of content, presentation and editing varies widely among chapters, sometimes falling below that expected in a book from a major publisher.