The constitutive law of plastic deformation expresses the effects of material behavior and properties for stress analysis in the design of manufacturing technology and product service behavior, for materials testing, and for the maintenance of structural and machine components. The book represents the state of the art, but the editors do not rule out other concepts of constitutive laws. There are many different facets of the same problem and as many answers; the right one is the one that gives the most practical solution, the one that best serves the specific problem