A survey is made of changes in the technical status of a number of western world copper extraction and refining operations over the past 20 years. Specific developments in pyro- and hydro- metallurgy and refining practices are identified together with factors in the changing environment of the industry which has influenced their adoption._x000D_
Nickel extraction and refining is similarly discussed._x000D_
The replacement of traditional technology by more attractive alternatives has occurred in a considerable number of operations. The develop- ment and status of new continuous smelting processes, advances in hydrometallurgy and refining innovations which emerged during the 1960s and early 1970s is discussed. The varying experience in commercial acceptance of these new technologies is noted._x000D_
Finally some possible future directions are canvassed for both operators and the research and development institutions.