Covers both equilibrium and non-equilibrium phenomena. Chapters challenges to be answered by current or future researchers and innovators in industry. Each chapter reviews major achievements in scientific understanding on the subject. During the last thirty years, there have been dramatic changes in the steel industry in terms of the quality of products, processing technology, energy efficiency, and environmental factors. The foundation of pyrometallurgy and the major operations in the steel industry is high temperature physical chemistry. This book focuses on key topics that are relevant to the reduction, refining solidification steps in the steel industry. It considers both equilibrium and non-equilibrium phenomena relevant to the processing of metals in general, and steel in particular, at high temperatures.