The history of industrial application of explosion for metal treatment, initially designed for metal hardening, spans almost half a century. The main body of achievements in the industrial application of explosion energy is based on the researches, which were made approximately since 1950. By being cost-effective and possessing unique technical capabilities, explosion metal treatment (EMT) has been developed in more than twenty directions, and even today it attracts the attention of many specialists. At the same time, production engineers who need to use this unusual source of energy for metal treatment face difficulties in applying previous experience for solving problems raised by new technology. The results of studies and technological solutions are scattered in many publications and monographs, the last one published in the early 90s, and usually relate only to specific uses of EMT. This complicates assessment of the state-of-the-art of EMT and selection of an appropriate technology for particular production conditions. This book is the first one on the theory and practice of EMT in Ukraine that solves, to a substantial degree, the above-mentioned problems. It gives an analysis of theoretical and applied aspects of using explosion energy in industry, in particular in welding production, mechanical engineering, industrial building construction and so on and is based on results obtained mainly by the author and his colleagues at the E O Paton Electric Welding Institute (PWI) of the National Academy of Sciences of Ukraine (Kiev), as wells as in other research centres.