This book is about the theoretical, experimental and computational aspects of disordered materials over a broad range of compositions. It deals with the structural characterization of glasses, liquids and solids by various techniques, and guides the reader how to interpret those data. The fields involved are broad, spanning from fundamental physical chemistry and physics to bio-tech and materials design. The introductory section (1) serves the reader with fundamental physical principles on different types of disorder, the atomic structure, and transition processes. The technical focus of the book is covered in section (2) which gives an overview of the most popular techniques for studying the structure of disordered materials, as there are Neutron and x-ray diffraction, NMR and Raman scattering. These are undoubtedly key techniques in the modern scientist's toolbox. For the first time, these methods are discussed with respect to their application under extreme conditions which has obtained increasing prominence in the materials and energy fields. For example, the use of high pressure as a way to make atomic structure itself an experimental variable has revealed itself to be a powerful means to probe structure/property relationships in a very direct manner. It is not surprising that it is often found difficult to interpret experimental data on these systems. Therefore section (3) serves an overview of modern computational methods for combining information from diverse data sets, building atomistic models, and testing hypotheses is needed. It presents inverse methods that fit date versus predictive simulations or ab initio calculations. The authors list the most successful methods and describe how they are applied to different sets of materials, including examples. They also show how to combine date from different techniques. This reference provides a comprehensive overview to those interested in the structural studies of disordered materials, as there are post-graduate and post-doctoral researches, but also for scientists aiming to develop research programs in the area of disordered material science in both solid and liquid systems, or searching for inspiration on methodology from other disciplines. The text could also provide good material for advanced final year undergraduate courses in materials characterisation.