This book describes the growing field of multi-criteria decision making (MCDM) as applied to materials selection in product design. Useful in academic and research contexts, as well as to practitioners in materials engineering and design, it aids readers in producing successful designs by improving the decision-making process in materials selection. It is a constant challenge for designers, even when educated in the fundamentals of materials and mechanical engineering, to select the best materials to satisfy complex design problems. Current approaches to materials selection range from the use of intuition and experience to computer-based methods including electronic databases and search engines. Increasingly, MCDM methods are proving effective in materials selection for complex design problems. These methods supplement existing quantitative methods, such as selection charts, by allowing simultaneous consideration of design attributes, component configurations and types of material. It discusses the rationale for optimal materials selection in the context of achieving the best engineering design. It describes methodologies for supporting enhanced decision-making in materials selection. It includes end-of-chapter review questions and practical case studies from biomedical and aerospace engineering applications.