Deformable solids, that is to say, those which undergo changes in geometry when subjected to external loads or other types of solicitations, as well as other related topics are the focus of this book. Within the main field, this text deals with advanced linear elasticity and plasticity approaches and the behavioural study of more complex types of materials. This includes composites of more recent manufacture and others whose material characterisation has only recently been possible. It also describes how linear elastic behaviour extends to anisotropic materials in general and how deformations can result in small or large strain components. The information on plastic behaviour expands to include strain hardening of the materials. Amongst other new topics incorporated into this volume are studies of hyperelastic materials, which can represent elastomeric and some types of biological materials. A section of the book deals with viscoelastic materials, i.e. those who deform when subjected to long-term loads. The behaviour of viscoplasticity, as well as elasto-viscoplasticity, describes well other types of materials, including those present in many geotechnical sites. The objective of this volume is to present material that can be used for teaching continuum mechanics to students of mechanical, civil or aeronautical engineering. In order to understand the contents the reader only needs to know linear algebra and differential calculus. Examples have been included throughout the text and at the end of each chapter, exercises are presented which can be used to check on comprehension of the theoretical information presented.