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Various X-ray diffraction analyses have been reported over 40 years for lipid systems and lipid dispersions. X-ray diffraction (XRD) emphasizes the crystalline nature and polymorphic transitions of lipids [111]. In the formulation development of most lipids, surfactants and drugs are polymorphic, and transformation may occur. Therefore, XRD provides a clear-cut demonstration of polymorphic transition of lipid samples, which is useful in the dispersion stability [111]. The physical attributes are the fundamental feature of lipid carriers for stable dispersions. The relation between physical aspects and dispersion stability and drug loading capacity inside the carrier system changes with the change in polymorphic forms. It is evident in literature that XRD analysis is employed in several lipidic drug delivery nanosystems including lamellar, hexagonal, and cubic phases [112]. A specialized x-ray scattering technique is available to identify the crystal lattice in aqueous dispersion. This technique is known as small-angle x-ray scattering.