The development of a sustainable transport will embrace a balance between resources, technology and environment. In this context, improved performances, increased efficiency and reduced material consumption represent the main current challenges addressed to research regarding new materials, energy saving and sustainable development. The optimal operation and efficiency of electrical machines used as primary and auxiliary sources in vehicles propulsion are closely related to their magnetic materials performance. This book, organized into four chapters, covers theoretical and experimental aspects regarding the characterization of soft and hard magnetic materials used in the construction of electrical machines for transportation. It approaches issues concerning the sustainable transport trends in correlation with material requirements, magnetization processes developed in magnetic materials, methods for characterization of soft and hard magnetic material properties and assessment of soft magnetic materials efficiency. The book is particularly useful for students and engineers in electrical, mechanical and materials engineering.