The publication contains the papers of the International Conference on Metal Structures held on 3-5 April 2003 in Miskolc Hungary. The conference made it possible to collect and discuss the newest research results in the following fields: Materials and fatigue of welded joints, thin-walled structures, tubular structures, frames, plates and shells, special optimization problems, applications, applied mechanics. The book contains 58 papers from 20 countries and provides an important reference for civil and mechanical engineers, architects, designers and fabricators.