Publisher Summary This chapter describes three alternative techniques for the cytochemical characterization of the components (membrane associated or not) that are exposed by freeze-fracture. The first, fracture-label permits the labeling of plasma and intracellular membranes (as well as cytoplasms and nucleoplasms) after freeze-fracture. The second, fracture-permeation explores the compactness of cytoplasmic and nucleoplasmic matrices in glutaraldehyde fixed cells. The third, label-fracture relates directly the surface labeling of a membrane to its freeze-fracture morphology. Freeze-fracture splits and exposes plasma membranes and intracellular membranes; in addition, cross-fracture exposes components of both cytoplasms and nucleoplasms. As conventional freeze-fracture is performed under vacuum, the molecules it exposes cannot be labeled because the specimens are frozen and inaccessible inside a vacuum chamber. Freeze-fracture is revealing itself as the least damaging method to expose receptors and antigens for labeling. Its random course ensures the steric availability of plasma and intracellular membranes, of cytoplasm and nucleoplasm components, as well as of extracellular matrices.