Ultrahigh Pressure Metamorphism (UHPM) is a fast growing discipline that was established 25 years ago after discoveries of high pressure minerals, coesite and diamonds. The current explosion of research on UHMP terranes reflects their significance for understanding large scale mantle dynamics, major elements of plate tectonics such as continental collisions, deep subduction and exhumation, mountains building, geochemical recycling 'from surface to the core', and a deep storage of light elements participating in green-house effects in the atmosphere. This book provides insights into the formation of diamond and coesite at very high pressures and explores new ideas regarding the tectonic setting of this style of metamorphism. - Important, authoritative and comprehensive one-stop resource for the growing ultrahigh pressure metamorphism UHPM research community - A forward-looking approach founded upon a detailed historical perspective on UHPM presents the trends in discovery, methodology and theory over the last 25 years, allowing readers to gain a clear understanding of the current trends and the approaches that will shape the science in the future - A highly diverse set of articles, covering a wide range of methods and sub-disciplines