Comprising two volumes, this publication classifies and systematizes data on phase transformations of 2263 elements and compounds under high pressure (at least 0.1 GPa). It includes data on new materials and compounds synthesized under high pressure. The book devotes a separate paragraphs to each compound with a bibliography that includes information on the behaviour of the material under normal pressure. It makes a critical analysis of experimental data on melting, first- and second-order phase transitions, crystal structures and phase diagrams.