The key to seismic design of structures lies in the controlled dissipation of seismic energy during an earthquake. A measure of this energy dissipation is the ductility of the structure, based on plastic deformations. Although it is generally accepted that steel structures have good ductility, through the observation of recent earthquakes it has been realised that this ductility can be undermined by the occurrence of local and global plastic buckling of structural members. This book is a state-of-the-art report on the ductility of steel structures, containing a comprehensive review of the technical literature available, and presenting the results of the authors' own extensive research activities in this area. Analytical and numerical methods are described, and a wealth of practical information is provided. Ductility of Seismic-Resistant Steel Structures will be of great use to advanced students, researchers, designers and professionals in the field of civil and structural engineering.