There are many books on composite material analysis, but most cover mainly continuous fiber materials, rather than those filled with discontinuous fibers, which are particularly attractive for large-volume and low-cost applications. This book provides the theoretical and practical background to design and use discontinuous fiber-reinforced polymer materials, with an emphasis on structural parts for the automotive industry. Moreover, the product of years of collaborative work between industry and academia is presented in an easy-to-use, comprehensive manner. The information provided makes it possible for someone with an engineering background to understand the micromechanics of discontinuous fiber-reinforced materials and, hence, analyze the structural performance of components designed with such materials. The book employs a practical approach to cover the key, unique capabilities that are critical for a successful structural analysis of discontinuous fiber-reinforced polymer structures: -Process simulation to estimate the condition of fibers in the finished parts, i.e., fiber length, orientation, and concentration -Capability to measure micro structure, i.e., fiber length distribution, fiber orientation tensors, and fiber concentration, etc. -Estimation of material properties in the part based on fiber condition, as well as environmental conditions such as temperature A broad range of areas is included, such as joining and assembly.