This text presents the techniques for a wide set of applications, ranging from the problems of size and shape optimization (historically the first to be studied) to topology and material optimization. Structural models are considered that use both discrete and finite elements. Structural materials can be classical or new. Emerging methods are also addressed, such as automatic differentiation, intelligent structures optimization, integration of structural optimization in concurrent engineering environments, and multidisciplinary optimization. This text should be of interest to researchers and designers in industries such as aerospace, automotive, mechanical, civil, nuclear, naval and offshore. It provides a reference for advanced undergraduate or graduate courses on structural optimization and optimum design.