It is obvious that no single technique can give complete structural information for each component of a fluid membrane system. However, in recent years the potential of X-ray scattering methods in probing peptide/lipid complexes, i.e., the membrane as well as the peptide structure, has been shown to be almost solely limited by the nonuniformity or patchiness of the peptide/lipid system itself (Qian et al. 2008; Salditt et al. 2006) . Therefore, if samples of suitable quality can be obtained, the potential of a simultaneous analysis at the molecular scale of the incorporated peptide species, the surrounding lipid matrix, and the peptide/lipid interactions underlines the power of this analytical method. In addition, X-ray scattering is compatible with the fluid membrane state and capable of providing information for both dimensions of the lipid bilayer space.