The pyrometallurgical processing of copper varies worldwide with respect to the charge materials, process, operating parameters, and the physical shape, size, and orientation of the vessel. Plant operations may be either batch, semi-continuous, or fully continuous to produce blister copper or other end product. The paper provides a compendium of hot metal practice for the multi-billion dollar global copper industry. The specialized sector, involving smelting and converting of copper-bearing materials, addresses commercially proven systems and alternative technologies. Five producers, namely, Chile 21.7%, China 11.4%, USA 10.7%, Japan 10.2%, and Russia 6.1%, accounted for the majority of primary refined copper in 2002. The writers reviewed the operations of 220 copper smelters worldwide which is in sharp contrast to nickel smelters which presently number about 50. A comparison of flash converting practices for Ausmelt, Inco, Kennecott, and Mitsubishi is included after summarizing known hot metal systems. For completeness, a section outlines the principles of copper electrorefining which go hand in glove with the front end pyrometallurgical treatment. The comprehensive paper, which may serve as a reference source, is analogous to a treatise since the broad and extensive coverage has international dimensions. Issues such as primary and secondary smelting, process variations due to either sulphidic or other copper-containing feedstock, marketing of the product mix, fugitive fixation such as production of sulphuric acid, and recovery of by-products such as precious metals, selenium, and tellurium are not addressed herein. Selected references illustrate smelting principles, competing technologies, and future trends in this vital segment of the economy. (C) 2003 Elsevier Ltd. All rights reserved.