Surface properties of metallic solids are of great technological interest. Their influence is felt in areas as diverse as catalysis, corrosion and the plasma stability in magnetic-confinement fusion reactors. In this paper a new surface analytic capability is reviewed which can provide a unique picture of a metallic surface by directly imaging, in atomic resolution, the spatial distribution of its constituent species and their depth distribution within the near surface region. After thoroughly reviewing the experimental technique and emphasizing design parameters and constraints, the analytic capabilities and limitations of the technique are discussed in detail. Examples are given of surface and near surface compositional analysis and the ability to obtain angstrom resolved depth profiles of implanted species having energies less than 100 eV. Although essentially a research technique requiring special sample preparation, the anticipated practical applications of Imaging Atom-Probe Mass Spectroscopy are numerous, ranging from metallurgical studies of grain boundary segragation and pre-precipitate clustering in alloys, to the direct imaging of constituent atoms within large, biological active molecules.