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In computer graphics, two types of geometric representations are widely used: surfaces and volumes. Surfaces are infinitely thin skins defining the boundary of an object, and have been successful in modeling realistic appearances. However, their lack of information about the solid nature of objects make them inadequate for many applica-tions. Volumes represent the entire solid geometry of an object in a three-dimensional grid. Volumes, however, are inefficient and cannot achieve high resolutions since they must maintain information about internal geometry that is not pertinent to rendering realistic appearances. We have created a new, hybrid data structure, the volumetric surface, which com-bines the benefits of surfaces and volumes. A volumetric surface represents solid ma-terials in a thin region near the surface of an object in an efficient, multi-resolution data structure. Volumetric surfaces are thus designed to exploit the coherency of roughly surface aligned-layers of materials which are ubiquitous in real-world mate-rials. Examples of such materials include wood, stone, and building facades