When this volume was first published, in 1969, plastic theory was the most modern method of structural analysis, and it made possible the direct design of steel frames in a way not available with only elastic methods. It is now recognized that this theory is also fundamental to structural design in materials such as reinforced concrete and aluminium. This is the first volume of a two-volume work by Professors Baker and Heyman that expounds and illustrates the methods of plastic design. Volume 1 gives the elements of the theory and covers the needs of most undergraduates and designers. A special feature of this work is the large number of exercises (140 in all) with answers. Volume 2 deals with advanced topics of theoretical analysis and practical design. The examples and the methods presented herein are extremely valuable to the engineer. The quality of the writing makes Professors Baker and Heyman's book a pleasure to read.