Over the past few years there has been a significant growth in the commercial application of a variety of processes which are all essentially based upon the very rapid heat treatment of powdered solid material in dilute gas suspensions. The objective of flash heating is usually to create a desirable product by means of physical and/or chemical transformations in the solid phase, usually with a high degree of control and with lower specific energy consumption than dense phase systems. Examples of successful flash reaction processing are to be found in the areas ofpyrometallurgy, mineral processing, plasma processing and, most recently, rapid prototyping. These developments have been based on, and have inspired, an expansion in fundamental research activities. As our understanding of flash reaction technology improves so does the need increase for the review of progress and the dissemination of accumulated knowl­ edge. Previous stocktaking on selected areas of flash reaction technology occurred in 1988 and can be found in the proceedings of three conferences held in that year: Flash Reaction Processes, Eds. D.G.C.Robertson, H.y'Sohn and N.J.Themelis, published by the Center for Pyrometallurgy, University of Missouri-Rolla, Rolla, MO 65401-0249; Production and Processing of Fine Particles, Ed. A.J .Plumpton, Pergamon Press, LeN 88-22755; High Temperature Dust-Laden Jets in Plasma Technology, Eds. O.P.Solonenko and A.I.Fedorchenko, VSP, Utrecht, ISBN 90- 6764-120-0.