This book represents a collection of papers presented at the NATO Advanced Research Workshop (NATO/ARW) on "Science and Technology of Rapid Solidification and Processing", held at Hotel Thayer, West Point Military Academy, New York, N. Y. , during June 21-24, 1994. The workshop was attended by over forty scientists representing several NATO member countries as well as representatives from Japan, China (PRC), Taiwan and India. The purpose of this NATO/ARW conference was to review the major advances made in most recent years in both the theoretical and experimental areas of rapid solidification technology and processing. In accordance with the NATO/ARW format, the agenda for the conference was so arranged to offer in depth presentation of the latest developments in the subject area as well as to encourage follow-up discussions by the participants. There was seven sessions each opened with a lecture by an invited guest speaker. Sessions 1-4, covered two days of the conference and focused mainly on Processing Technologies of Rapid Solidification and Thermodynamic Properties (Practical Applications). Sessions 4-6 concentrated on Thermodynamics of Metastable Alloys, Relaxation, Diffusion, Magnetic and Electric Properties (Fundamentals). Session 6 was devoted to the Structural Characterization of Supercooled Melts, Ultra Fine Polycrystalline Materials (New Innovations and Techniques). There were two equally important aspects of this NATO/ARW conference which must be mentioned. Firstly, this is the first NATO/ARW conference on Science and Technology of Rapid Solidification and Processing held in the United States.