The rapid development of proteomics has been made possible primarily by the progress in analytical and preparative separation methods. Biological systems are so complex that the separation procedures employed must be highly efficient as well as highly selective. The latter requirement is best met by affinity separations based on molecular recognition. The present review critically discusses the properties of the affinity sorbents employed in proteomics, namely, agarose gels, dextrans, modified methacrylate and acrylamide polymers, porous and nonporous silica, porous glass beads, monoliths, affinity membranes and magnetic beads. The physico-chemical properties of these materials, their preparation, application, approaches to their modification and their relative advantages and drawbacks are discussed.