T. H. NORTH Dept. of Metallurgy and Materials Science, University of Toronto. This volume documents the proceedings of the International Congress on Joining Research held under the auspices of the Canadian Council of the International Institute of Welding in Montreal, July 20/21 1990. This congress was sponsored by the Welding Institute of Canada, Oakville, Ontario. The study of joining is important, both from the fundamental and applied science points of view. Joining encompasses a wide range of areas, from welding processes, through welding metallurgy and materials science, to non-destructive testing, automation and field construction. Welding has sometimes been referred to as some curious combination of art and science. Certainly, from a university research perspective, the welding area is remarkably difficult to tackle because it is extremely difficult to sift out the critical variables. As a result, it is sometimes difficult to separate the real from the imaginary in any detailed evaluation of the joining literature. I sincerely hope that the authoritative contributions in this volume will sweep away any confusion that exists in the mind of the reader.