The book deals with both theory and practice for design of welded steelwork, and thus, is intended to be of deep interest and value not only to the design engineers and welding engineers in the workshop, but also to the educators and students in the academic field. The material covered in the text represents accumulated knowledge gained through researchers in different countries, primarily in Europe and America, and published in the form of books including published articles, supplemented by the author?s own experience in design and construction of welded structures.