This beginning text has been written for students of architecture, building construction, and related technologies. It is intended to provide the material for a first course in structures, treating the essential topics in statics and mechanics of materials and providing an introduction to structural analysis. The presentation is basically quantitative, and it will be most effective when used in conjunction with a book emphasizing a qualitative approach to structural behavior. It is assumed that the student has a background in materials and methods of construction from prior coursework or individual experience. Chapter 5 provides a very brief review of the essential characteristics of a few structural materials but is not sufficient in either depth or scope. A minimal background in calculus and physics has also been assumed for students of this material. Most derivations of the equations have been placed in the appendices, because they usually are not absolutely essential to the use of the equations themselves. Better students, however, will gain additional understanding and insight by consulting these derivations as they are referenced. As with previous editions, all sections contain examples and problems using both SI and customary units. It is hoped that instructors will be able to use either system with minimal confusion. I do not recommend using a mix of units during the first course in structures, because it might hinder the proper understanding of "first principles" that is so essential to the student's future study and practice. My school, for example, teaches the first course exclusively in SI units and the remaining ones in customary units. Chapter 1 has been revised and expanded to include additional material regarding why architects must be well versed in the science and art of structural behavior as well as to include some guidelines concerning structural system selection. I think teachers sometimes forget how complex this subject appears to the beginner, and how easy it is to get overwhelmed by the introduction of so many new (and, at first, seemingly unrelated) concepts. Chapter 1 should be read at the outset and then more thoroughly discussed after the study of equilibrium, bending, buckling, and other topics. By expressed demand, Chapters 2 and 12 hake been expanded to include additional material on graphical statics. Section 2.17 treats the graphical analysis of some relatively complicated structures and was placed in this chapter because itisstatics, but I recommend treating this materialaftercovering the graphical solution of trusses in the new Section 12.3. I usually treat trusses near the end of the first semester, because I believe that trusses are not "simple structures" and that their behavior can be understood best after bending and buckling have been discussed. This approach also has the positive feature of bringing the student back to a consideration of basic equilibrium principles after a possible period of reduced emphasis. I am grateful to Professors Madan Mehta, Jane Murphy, Pat Tripeny, and Falix T. Uhlik for reviewing material and providing helpful suggestions. I am especially appreciative of the continued illustrative contributions and advice of Patrick Pinnell. I also wish to thank the production editor, Christine Buckendahl; the production coordinators, C rolyn Greene and Susan Free; the graphic artist, David Tebera; and the copy editor, Wesley Morrison, for their patience and tireless efforts on my behalf. As stated in prior editions, please inform me of any errors you find; don't assume that I've already been notified. Thank you in advance for your suggestions and assistance. - R. E. ShaefferShaeffer, Ronald E. is the author of 'Elementary Structures for Architects and Builders', published 0013 under ISBN 9780130928771 and ISBN 0130928771.