This book presents basic structural deformation and stress analysis as applied to optical systems. It provides the tools for first-order analyses required in the design concept phase before handling the intricate details of a full-up design. While finite element analysis is paramount to a successful design, the purpose of this text is not to use finite element analysis to validate the hand analysis, but rather to use hand analysis to validate the finite element models. The hand analysis forces a discipline that is paramount in the understanding of structural behavior. Presuming that the reader has a working knowledge in the strength of materials, the text applies engineering principles to opto-structural analysis. John W. Pepi received his undergraduate education from Tufts University, graduating with a Bachelor of Science degree in Civil Engineering in 1967. He obtained a Master of Science degree in Structural Engineering in 1968 from Northwestern University. He has been employed with L-3 Technologies SSG for the past fifteen years as a lead staff mechanical engineer for precision, lightweight, space-based optical systems. Prior to his employment at L-3 he was employed at Lockheed Martin and was extensively involved as lead engineer for the successfully launched AIRS satellite program for JPL/NASA Goddard Space Flight Center. Prior to that assignment, he held the positions of lead engineer, chief engineer, department manager, and program manager for large optical systems at ITEK Optical Systems, where he worked for 22 years directing the work of up to 55 individuals. His last assignment for the Keck Telescope led to the discovery of delayed elasticity effects in certain ceramics. John is an internationally recognized authority on lightweight mirror design and a member of several international ground-based large-telescope oversight committees. He is an SPIE Fellow and is the author of more than one dozen publications on lightweight optics and mirror design principles, including the book Strength Properties of Glass and Ceramics, SPIE Press (2014), and has been an instructor for SPIE at its international meetings.