The technique is described for use of x-ray double crystal diffractometry for analysis of epitaxial structures. This method has been shown to be very useful for characterizing a wide variety of configurations, ranging from single epitaxial layers to damaged superlattices. It yields depth profiles of structure factors and strains relative to the substrate, which can be directly related to layer thicknesses and compositions. Information about dislocations and random atomic displacements is also present. The key to this technique is computer fitting of the x-ray data with a model for the diffraction process, utilizing trial profiles for the strain and structure factors of the epitaxial layers. In the work to be presented a kinematic model for the diffraction is used. The technique is demonstrated with analyses of an Alx Ga(1−x) As single layer on GaAs, an AlSb/GaSb superlattice on GaSb, epitaxial CoSi2 on Si, and ion-implanted and annealed AlxGa(1−x)As superlattices on GaAs.