Fewster (Philips Analytical Research Center, UK) discusses the X-ray scattering methods used for the structural analysis of a range of semiconductor materials, emphasizing those structural properties that influence physical properties. The text covers the basic structural characteristics of materials, the theory of X-ray scattering, the principles of the instrumentation, and a number of examples of analyses. The analysis section covers bulk semiconductor materials, nearly perfect semiconductor multi-layer structures, mosaic structures, partially relaxed multi-layer structures, laterally inhomogeneous multi-layers, textured polycrystalline semiconductors, and nearly perfect polycrystalline materials.