The use of super-critical fluids as media for the formation of powdered materials is one of recent developments of supercritical fluid technologies. Driving force for understanding and design of a high pressure micronization processes is the knowledge of solid-liquid-gas (S-L-G) equilibrium. The results of experimental research verify the theory that the type of S-L-G equilibrium could be used to predict the applicability of high pressure micronization and to optimize the choice of operation parameters. It is very important to understand the influence of pressure on the melting point of the substance in the presence of gas and phase equilibrium data of the system. This work aims to review the published literature dealing with determination of melting points under pressure. Paper describes different methods and apparatus for the determination of S-L-G transitions and different systems substance/super-critical fluids. (C) 2010 Elsevier B.V. All rights reserved.