Elastoplastic behavior has long been part of the constitutive models incorporated in most computer codes, used in the design of civil and mechanical engineering structures. Elastoplastic Modeling offers a compact presentation of the fundamentals of classical elastoplastic modeling, the basis for many engineering applications currently implemented. This book provides a general background to enhance understanding of the modeling assumptions that govern the rationales of these applications. With this understanding comes the ability to assess their validation range and propose possible improvements. An instructive approach replaces excessive mathematical developments with a semi-phenomenological method, where mathematical modeling is driven by − and derived from − experimental observations. A logical track is followed, starting from material behavior modeling and leading to the analysis of the anelastic response of systems, subjected to quasi-static loading processes.