The development of intense synchrotron radiation sources during the last twenty years has enabled several types of x-ray spectroscopy and scattering techniques to come into practical use. One of the most significant methods for the characterization of extremely dilute samples is high resolution x-ray absorption-edge spectroscopy. The technique is usually divided into two separate methods according to whether the x-ray absorption near edge structure (XANES) or the extended x-ray absorption fine structure (EXAFS) is analyzed. XANES features are due mainly to bound-state electronic transitions just below, and on the low energy side of the edge, and to multiple scattering resonances on the top of the edge and at somewhat higher energies. EXAFS features are oscillations due to ejected photoelectron back scattering interference processes in the close vicinity of the absorber atom. XANES analysis is used to determine atom valence, atom site distortion from regular geometries, and other details of the atom site. EXAFS features can be analyzed to recover interatomic distances between the absorber atom and its first few shells of neighbors, as well as the number and types of these neighbors. Together these techniques can provide an atomspecific probe of die short-range structure within almost any type of condensed matter.